soc/amd/common/block/pi: Add missing include stdbool.h

BUG=b:179699789
TEST=build morphius

Signed-off-by: Raul E Rangel <rrangel@chromium.org>
Change-Id: I298ce1ee436a5c8eb8375dc5fe55665bbf977463
Reviewed-on: https://review.coreboot.org/c/coreboot/+/57619
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Felix Held <felix-coreboot@felixheld.de>

src/soc/amd/common/block/pi/image.c

@@ -2,6 +2,7 @@
 
 #include <agesa_headers.h>
 #include <amdblocks/image.h>
+#include <stdbool.h>
 
 /* Check if the image has the desired module. */
 static bool validate_image(void *module_chain, const char module_signature[8])