Revert "[nrf noup] boards: nrf54l15: Disable FPROTECT"

This reverts commit d82956a.

Signed-off-by: Jamie McCrae <[email protected]>

Author: nordicjm

boot/zephyr/boards/nrf54l15pdk_nrf54l15_cpuapp.conf

@@ -7,7 +7,4 @@ CONFIG_BOOT_MAX_IMG_SECTORS=256
 # Ensure that the SPI NOR driver is disabled by default
 CONFIG_SPI_NOR=n
 
-# TODO: below are not yet supported and need fixing
-CONFIG_FPROTECT=n
-
 CONFIG_BOOT_WATCHDOG_FEED=n