treewide: Drop bootm_headers_t typedef

This is not needed and we should avoid typedefs. Use the struct instead.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/common/spl/spl.c b/common/spl/spl.c
index 828f72f..1283f9e 100644
--- a/common/spl/spl.c
+++ b/common/spl/spl.c
@@ -260,7 +260,7 @@
 static int spl_load_fit_image(struct spl_image_info *spl_image,
 			      const struct image_header *header)
 {
-	bootm_headers_t images;
+	struct bootm_headers images;
 	const char *fit_uname_config = NULL;
 	uintptr_t fdt_hack;
 	const char *uname;