[nrf fromlist] zephyr: remove NRFX_WDT instance symbols

Removed from Zephyr.

Upstream PR #: 2507

Signed-off-by: Michał Stasiak <[email protected]>

Author: mstasiaknordic

boot/zephyr/Kconfig

@@ -1184,11 +1184,6 @@ config BOOT_WATCHDOG_FEED_NRFX_WDT
 	depends on SOC_FAMILY_NORDIC_NRF
 	# for nRF nrfx based implementation is available
 	imply NRFX_WDT
-	imply NRFX_WDT0
-	imply NRFX_WDT1
-	imply NRFX_WDT30
-	imply NRFX_WDT31
-	imply NRFX_WDT010
 
 config BOOT_IMAGE_ACCESS_HOOKS
 	bool "Enable hooks for overriding MCUboot's native routines"