cbfstool: Support 64bit addresses for flat images

SELF has the fields wired up for 64bit, but adding flat images cuts the
upper half.

Change-Id: I3b48b8face921e942fb0e01eace791ad3e1669a0
Signed-off-by: Patrick Georgi <patrick@coreboot.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/80576
Reviewed-by: ron minnich <rminnich@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

util/cbfstool/common.h

@@ -178,8 +178,8 @@ int parse_bzImage_to_payload(const struct buffer *input,
 			     char *cmdline, enum cbfs_compression algo);
 int parse_flat_binary_to_payload(const struct buffer *input,
 				 struct buffer *output,
-				 uint32_t loadaddress,
-				 uint32_t entrypoint,
+				 uint64_t loadaddress,
+				 uint64_t entrypoint,
 				 enum cbfs_compression algo);
 /* cbfs-mkstage.c */
 int parse_elf_to_stage(const struct buffer *input, struct buffer *output,