Revert "[nrf noup] boards: arm: nrf9131ek: enable tfm"

This reverts commit 8955e01.

Signed-off-by: Jonathan Nilsen <[email protected]>

Author: jonathannilsen

boards/nordic/nrf9131ek/Kconfig.defconfig

@@ -5,21 +5,6 @@
 
 if BOARD_NRF9131EK_NRF9131 || BOARD_NRF9131EK_NRF9131_NS
 
-# By default, if we build for a Non-Secure version of the board,
-# enable building with TF-M as the Secure Execution Environment.
-config BUILD_WITH_TFM
-	default y if BOARD_NRF9131EK_NRF9131_NS
-
-if BUILD_WITH_TFM
-
-# By default, if we build with TF-M, instruct build system to
-# flash the combined TF-M (Secure) & Zephyr (Non Secure) image
-config TFM_FLASH_MERGED_BINARY
-	bool
-	default y
-
-endif # BUILD_WITH_TFM
-
 # For the secure version of the board the firmware is linked at the beginning
 # of the flash, or into the code-partition defined in DT if it is intended to
 # be loaded by MCUboot. If the secure firmware is to be combined with a non-