libflashrom: Add CPP guard to fix big-endian builds

Calm a compiler warning on big-endian builds about the unused static
flashrom_layout_parse_fmap(). The guard is ugly but gets the job done.
We should forbid endian-specific code in the future, I guess.

Change-Id: Id3f4a57e027f88cc469ed50312adddcc8af71a63
Signed-off-by: Nico Huber <nico.h@gmx.de>
Reviewed-on: https://review.coreboot.org/c/flashrom/+/33306
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
diff --git a/libflashrom.c b/libflashrom.c
index c5e56ae..fee60ff 100644
--- a/libflashrom.c
+++ b/libflashrom.c
@@ -386,6 +386,7 @@
 #endif
 }
 
+#ifdef __FLASHROM_LITTLE_ENDIAN__
 static int flashrom_layout_parse_fmap(struct flashrom_layout **layout,
 		struct flashctx *const flashctx, const struct fmap *const fmap)
 {
@@ -417,6 +418,7 @@
 	*layout = l;
 	return 0;
 }
+#endif /* __FLASHROM_LITTLE_ENDIAN__ */
 
 /**
  * @brief Read a layout by searching the flash chip for fmap.