tools: omapimage: Fix size in header

The size field in GP header that is expected by ROM is size of the
image + size of the header. But omapimage generates a gp header
only with size of the image as size field. Fix it

Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
diff --git a/tools/omapimage.c b/tools/omapimage.c
index 7198b33..e31b94a 100644
--- a/tools/omapimage.c
+++ b/tools/omapimage.c
@@ -143,7 +143,7 @@
 	toc++;
 	memset(toc, 0xff, sizeof(*toc));
 
-	gph_set_header(gph, sbuf->st_size - OMAP_FILE_HDR_SIZE,
+	gph_set_header(gph, sbuf->st_size - OMAP_CH_HDR_SIZE + GPIMAGE_HDR_SIZE,
 		       params->addr, 0);
 
 	if (strncmp(params->imagename, "byteswap", 8) == 0) {