boot: android: handle boot images with missing DTB

607b07554e2 removed the check on the return status of the
android_image_get_dtb_img_addr call from android_image_get_dtb_by_index,
which results in null pointer accesses shortly after when trying to
check the header of a nonexistent DTB.

Fixes: 607b07554e2 ("android: boot: move to andr_image_data structure")
Signed-off-by: Sam Day <me@samcday.com>
Reviewed-by: Mattijs Korpershoek <mkorpershoek@baylibre.com>
Link: https://lore.kernel.org/r/20250123-android-handle-no-dtb-v1-1-1cb7373247da@samcday.com
Signed-off-by: Mattijs Korpershoek <mkorpershoek@baylibre.com>
diff --git a/boot/image-android.c b/boot/image-android.c
index fa4e14c..1746b01 100644
--- a/boot/image-android.c
+++ b/boot/image-android.c
@@ -696,7 +696,10 @@
 	ulong dtb_addr;		/* address of DTB blob with specified index  */
 	u32 i;			/* index iterator */
 
-	android_image_get_dtb_img_addr(hdr_addr, vendor_boot_img, &dtb_img_addr);
+	if (!android_image_get_dtb_img_addr(hdr_addr, vendor_boot_img,
+					    &dtb_img_addr))
+		return false;
+
 	/* Check if DTB area of boot image is in DTBO format */
 	if (android_dt_check_header(dtb_img_addr)) {
 		return android_dt_get_fdt_by_index(dtb_img_addr, index, addr,