spl: Add a parameter to spl_parse_image_header()

Instead of using the global spl_image variable, pass the required struct in
as an argument.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/common/spl/spl_onenand.c b/common/spl/spl_onenand.c
index 1a28a84..8d2c51b 100644
--- a/common/spl/spl_onenand.c
+++ b/common/spl/spl_onenand.c
@@ -26,7 +26,7 @@
 	/* Load u-boot */
 	onenand_spl_load_image(CONFIG_SYS_ONENAND_U_BOOT_OFFS,
 		CONFIG_SYS_ONENAND_PAGE_SIZE, (void *)header);
-	ret = spl_parse_image_header(header);
+	ret = spl_parse_image_header(&spl_image, header);
 	if (ret)
 		return ret;
 	onenand_spl_load_image(CONFIG_SYS_ONENAND_U_BOOT_OFFS,