selfload: check target memory type in selfload_check

Currently, selflock_check() verifies that the binary is loaded in an
usable RAM area.

Extend its functionality so we can also check that BL31 is loaded in
a manually reserved area, and fail early if the range is not protected.

Change-Id: Iecdeedd9e8da67f73ac47d2a82e85b306469a626
Signed-off-by: Ting Shen <phoenixshen@google.com>
Reviewed-on: https://review.coreboot.org/c/31122
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Julius Werner <jwerner@chromium.org>

src/arch/arm64/arm_tf.c

@@ -19,6 +19,7 @@
 #include <arch/transition.h>
 #include <arm_tf.h>
 #include <assert.h>
+#include <bootmem.h>
 #include <cbfs.h>
 #include <program_loading.h>