MLK-20559-6 f_sdp: Support searching and loading FIT or container image

MLK-20559-6 f_sdp: Support searching and loading FIT or container image

Add support to f_sdp to search and load iMX8 container image or iMX8M
FIT image by new UUU command SDPV.

When using the SDPV, the uuu will continue to send out data after first
level boot loader used by ROM. This means uuu won't skip to the offset
of the second boot loader, and the padding data before second boot loader
will be sent out. So we have to search the FIT header or container header
in the buffer that SDP received.

The new BCD value is used by uuu to distinguish if the SPL supports the
SDPV.

Signed-off-by: Ye Li <ye.li@nxp.com>
(cherry picked from commit cddb0fde374769dccff44275a5072c5e28e41446)