Build: Fix stm32wba65i_dk platform build issues

- Use `tfm_s_bin` target, aligning with changes in the GNUARM toolchain.
- Updated logic for emulating `mcuboot_config.h` used by FWU partition.
- Move `BL2` before `secure_fw` because FWU partition depends on MCUBoot.

Signed-off-by: Anton Komlev <anton.komlev@arm.com>
Change-Id: I4a2935d68df52e9194c21ab7cf20aeecc63c5bb2
4 files changed