configs: synquacer: Use RAW capsule image instead of FIT

Since the recent commit;

 commit b891ff18 ("efi_loader: Force a single FMP instance per hardware store")

forces a single FMP instances for a storage, we can not
enable both RAW and FIT capsule image support at once.
Since RAW capsule image support is simpler than FIT,
enable RAW capsule image instead of FIT by default.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu@linaro.org>