feat(stm32mp1): add GUID values for updatable images

With the FWU multi bank feature enabled, the identification of
firmware image type is done using the image type GUID instead of
binary_type field.

Add GUID values for the FIP image which can be updated through
the FWU firmware update feature. The GUID values are used in
identifying the firmware images.

Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org>
Change-Id: If7d9356aa8d2bb3fbcbc87100e6972f1a1862921