drivers/intel/fsp1_1: Adjust check for FSP header revision

With FSP 1.1, all FSP blobs are forward-compatible with newer FSP 1.1
header files, so adjust the header revision check to ensure that the
FSP blob isn't newer than the header, rather than an exact version match.

This resolves a version mismatch issue with Braswell ChromeOS devices,
which ship with FSP blobs newer than the publicly-released blob (1.1.2.0),
but older than the current Braswell FSP 1.1 header (1.1.7.0).

TEST: build/boot google/cyan and edgar boards, observe no adverse
effects from using current FSP header (1.1.7.0) with the factory-
shipped FSP blobs (1.1.4.0/1.1.4.2).

Change-Id: I8934675a2deed260886a83fa34512904c40af8e1
Signed-off-by: Matt DeVillier <matt.devillier@gmail.com>
Reviewed-on: https://review.coreboot.org/21369
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
diff --git a/src/drivers/intel/fsp1_1/fsp_util.c b/src/drivers/intel/fsp1_1/fsp_util.c
index 34d6e48..0116ac2 100644
--- a/src/drivers/intel/fsp1_1/fsp_util.c
+++ b/src/drivers/intel/fsp1_1/fsp_util.c
@@ -79,7 +79,7 @@
 		return (FSP_INFO_HEADER *)ERROR_FSP_SIG_MISMATCH;
 
 	/* Verify the FSP Revision */
-	if (fsp_ptr.fih->ImageRevision != FSP_IMAGE_REV)
+	if (fsp_ptr.fih->ImageRevision > FSP_IMAGE_REV)
 		return (FSP_INFO_HEADER *)ERROR_FSP_REV_MISMATCH;
 
 	return fsp_ptr.fih;