boot: zephyr: stm32n6570_dk: define CONFIG_MULTIPLE_EXECUTABLE_RAM_REGIONS

Now that a dedicated symbol exists, make use of it.

Signed-off-by: Erwan Gouriou <[email protected]>

Author: erwango

boot/zephyr/boards/stm32n6570_dk_stm32n657xx_fsbl.conf

@@ -1,3 +1,5 @@
 CONFIG_STM32_MEMMAP=y
 CONFIG_BOOT_MAX_IMG_SECTORS_AUTO=n
 CONFIG_BOOT_MAX_IMG_SECTORS=4096
+
+CONFIG_MULTIPLE_EXECUTABLE_RAM_REGIONS=y