feat(boards/px4_fmu-v6c): add LSM6DSV16X support for Pixhawk6C

Enable the ST LSM6DSV16X as an alternative probe-based IMU on
Pixhawk6C.

The sensor is configured on SPI1 with chip-select PC13 and shares the
same CS and DRDY lines as the ICM42688P across all supported hardware
revisions. Board startup first probes the ICM42688P and then the
LSM6DSV16X, so only the IMU populated on a given board is started.

This change enables the LSM6DSV16X driver in the board configuration,
registers the device type in `spi.cpp`, and adds board sensor probing
for the new IMU.

Use rotation `-R 26` (`ROTATION_PITCH_180_YAW_90`) to match the sensor
orientation on the Pixhawk6C PCB.

Author: zebulon-86

boards/px4/fmu-v6c/default.px4board

@@ -22,6 +22,7 @@ CONFIG_DRIVERS_HEATER=y
 CONFIG_DRIVERS_IMU_BOSCH_BMI055=y
 CONFIG_DRIVERS_IMU_BOSCH_BMI088=y
 CONFIG_DRIVERS_IMU_INVENSENSE_ICM42688P=y
+CONFIG_DRIVERS_IMU_ST_LSM6DSV=y
 CONFIG_COMMON_LIGHT=y
 CONFIG_COMMON_MAGNETOMETER=y
 CONFIG_DRIVERS_POWER_MONITOR_INA226=y

boards/px4/fmu-v6c/init/rc.board_sensors

@@ -15,8 +15,9 @@ else
        bmi055 -G -R 4 -s start
 fi
 
-# Internal SPI bus ICM42688p
+# Internal SPI bus IMU (probe-based: LSM6DSV or ICM42688P on same CS)
 icm42688p -R 6 -s start
+lsm6dsv -R 26 -s start
 
 # Internal barometer on I2C4 (The same bus is also exposed externally, and therefore marked as external)
 ms5611 -X -b 4 -a 0x77 start

boards/px4/fmu-v6c/src/spi.cpp

@@ -41,6 +41,7 @@ constexpr px4_spi_bus_all_hw_t px4_spi_buses_all_hw[BOARD_NUM_SPI_CFG_HW_VERSION
 			initSPIDevice(DRV_GYR_DEVTYPE_BMI055,  SPI::CS{GPIO::PortC, GPIO::Pin14}, SPI::DRDY{GPIO::PortE, GPIO::Pin5}),
 			initSPIDevice(DRV_ACC_DEVTYPE_BMI055,  SPI::CS{GPIO::PortC, GPIO::Pin15}, SPI::DRDY{GPIO::PortE, GPIO::Pin4}),
 			initSPIDevice(DRV_IMU_DEVTYPE_ICM42688P, SPI::CS{GPIO::PortC, GPIO::Pin13}, SPI::DRDY{GPIO::PortE, GPIO::Pin6}),
+			initSPIDevice(DRV_IMU_DEVTYPE_ST_LSM6DSV, SPI::CS{GPIO::PortC, GPIO::Pin13}, SPI::DRDY{GPIO::PortE, GPIO::Pin6}),
 		}, {GPIO::PortB, GPIO::Pin2}),
 		initSPIBus(SPI::Bus::SPI2, {
 			initSPIDevice(SPIDEV_FLASH(0), SPI::CS{GPIO::PortD, GPIO::Pin4})
@@ -51,6 +52,7 @@ constexpr px4_spi_bus_all_hw_t px4_spi_buses_all_hw[BOARD_NUM_SPI_CFG_HW_VERSION
 			initSPIDevice(DRV_GYR_DEVTYPE_BMI055,  SPI::CS{GPIO::PortC, GPIO::Pin14}, SPI::DRDY{GPIO::PortE, GPIO::Pin5}),
 			initSPIDevice(DRV_ACC_DEVTYPE_BMI055,  SPI::CS{GPIO::PortC, GPIO::Pin15}, SPI::DRDY{GPIO::PortE, GPIO::Pin4}),
 			initSPIDevice(DRV_IMU_DEVTYPE_ICM42688P, SPI::CS{GPIO::PortC, GPIO::Pin13}, SPI::DRDY{GPIO::PortE, GPIO::Pin6}),
+			initSPIDevice(DRV_IMU_DEVTYPE_ST_LSM6DSV, SPI::CS{GPIO::PortC, GPIO::Pin13}, SPI::DRDY{GPIO::PortE, GPIO::Pin6}),
 		}, {GPIO::PortB, GPIO::Pin2}),
 		initSPIBus(SPI::Bus::SPI2, {
 			initSPIDevice(SPIDEV_FLASH(0), SPI::CS{GPIO::PortD, GPIO::Pin4})
@@ -61,6 +63,7 @@ constexpr px4_spi_bus_all_hw_t px4_spi_buses_all_hw[BOARD_NUM_SPI_CFG_HW_VERSION
 			initSPIDevice(DRV_GYR_DEVTYPE_BMI088,  SPI::CS{GPIO::PortC, GPIO::Pin14}, SPI::DRDY{GPIO::PortE, GPIO::Pin5}),
 			initSPIDevice(DRV_ACC_DEVTYPE_BMI088,  SPI::CS{GPIO::PortC, GPIO::Pin15}, SPI::DRDY{GPIO::PortE, GPIO::Pin4}),
 			initSPIDevice(DRV_IMU_DEVTYPE_ICM42688P, SPI::CS{GPIO::PortC, GPIO::Pin13}, SPI::DRDY{GPIO::PortE, GPIO::Pin6}),
+			initSPIDevice(DRV_IMU_DEVTYPE_ST_LSM6DSV, SPI::CS{GPIO::PortC, GPIO::Pin13}, SPI::DRDY{GPIO::PortE, GPIO::Pin6}),
 		}, {GPIO::PortB, GPIO::Pin2}),
 		initSPIBus(SPI::Bus::SPI2, {
 			initSPIDevice(SPIDEV_FLASH(0), SPI::CS{GPIO::PortD, GPIO::Pin4})
@@ -71,6 +74,7 @@ constexpr px4_spi_bus_all_hw_t px4_spi_buses_all_hw[BOARD_NUM_SPI_CFG_HW_VERSION
 			initSPIDevice(DRV_GYR_DEVTYPE_BMI055,  SPI::CS{GPIO::PortC, GPIO::Pin14}, SPI::DRDY{GPIO::PortE, GPIO::Pin5}),
 			initSPIDevice(DRV_ACC_DEVTYPE_BMI055,  SPI::CS{GPIO::PortC, GPIO::Pin15}, SPI::DRDY{GPIO::PortE, GPIO::Pin4}),
 			initSPIDevice(DRV_IMU_DEVTYPE_ICM42688P, SPI::CS{GPIO::PortC, GPIO::Pin13}, SPI::DRDY{GPIO::PortE, GPIO::Pin6}),
+			initSPIDevice(DRV_IMU_DEVTYPE_ST_LSM6DSV, SPI::CS{GPIO::PortC, GPIO::Pin13}, SPI::DRDY{GPIO::PortE, GPIO::Pin6}),
 		}, {GPIO::PortB, GPIO::Pin2}),
 		initSPIBus(SPI::Bus::SPI2, {
 			initSPIDevice(SPIDEV_FLASH(0), SPI::CS{GPIO::PortD, GPIO::Pin4})
@@ -81,6 +85,7 @@ constexpr px4_spi_bus_all_hw_t px4_spi_buses_all_hw[BOARD_NUM_SPI_CFG_HW_VERSION
 			initSPIDevice(DRV_GYR_DEVTYPE_BMI088,  SPI::CS{GPIO::PortC, GPIO::Pin14}, SPI::DRDY{GPIO::PortE, GPIO::Pin5}),
 			initSPIDevice(DRV_ACC_DEVTYPE_BMI088,  SPI::CS{GPIO::PortC, GPIO::Pin15}, SPI::DRDY{GPIO::PortE, GPIO::Pin4}),
 			initSPIDevice(DRV_IMU_DEVTYPE_ICM42688P, SPI::CS{GPIO::PortC, GPIO::Pin13}, SPI::DRDY{GPIO::PortE, GPIO::Pin6}),
+			initSPIDevice(DRV_IMU_DEVTYPE_ST_LSM6DSV, SPI::CS{GPIO::PortC, GPIO::Pin13}, SPI::DRDY{GPIO::PortE, GPIO::Pin6}),
 		}, {GPIO::PortB, GPIO::Pin2}),
 		initSPIBus(SPI::Bus::SPI2, {
 			initSPIDevice(SPIDEV_FLASH(0), SPI::CS{GPIO::PortD, GPIO::Pin4})