image: Fix Android boot image support

This patch makes the following changes:
- Set kernel entry point correctly
- Append bootargs from image to global bootargs instead
        of replacing them
- Return end address instead of size from android_image_get_end()
- Give correct parameter to genimg_get_format() in boot_get_ramdisk()
- Move ramdisk message printing from android_image_get_kernel() to
	android_image_get_ramdisk()

Signed-off-by: Ahmad Draidi <ar2000jp@gmail.com>
Cc: Tom Rini <trini@ti.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

common/image.c

@@ -1010,7 +1010,8 @@ int boot_get_ramdisk(int argc, char * const argv[], bootm_headers_t *images,
 		image_multi_getimg(images->legacy_hdr_os, 1, &rd_data, &rd_len);
 	}
 #ifdef CONFIG_ANDROID_BOOT_IMAGE
-	else if ((genimg_get_format(images) == IMAGE_FORMAT_ANDROID) &&
+	else if ((genimg_get_format((void *)images->os.start)
+			== IMAGE_FORMAT_ANDROID) &&
 		 (!android_image_get_ramdisk((void *)images->os.start,
 		 &rd_data, &rd_len))) {
 		/* empty */