raspberrypi4: Pin to using 6.12 kernel

Signed-off-by: Khem Raj <khem.raj@oss.qualcomm.com>

Author: kraj

conf/machine/raspberrypi4.conf

@@ -6,6 +6,12 @@ DEFAULTTUNE ?= "cortexa7thf-neon-vfpv4"
 require conf/machine/include/arm/armv7a/tune-cortexa7.inc
 include conf/machine/include/rpi-base.inc
 
+# 6.18 has removed 32bit config for rpi4 and expects it
+# to always use 64bit kernel even if rootfs is needed to be
+# 32bit. So we need multiconfig builds, and technically, 32bit
+# option for rpi4 should be gone
+PREFERRED_VERSION_linux-raspberrypi ?= "6.12.%"
+
 MACHINE_FEATURES += "pci"
 MACHINE_EXTRA_RRECOMMENDS += "\
     linux-firmware-rpidistro-bcm43455 \