x86: efi: payload: Make EFI payload build again

Since commit 73c5c39 "Makefile: Drop unnecessary -dtb suffixes",
EFI payload does not build anymore. This fixes the build.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/include/efi.h b/include/efi.h
index 1dbc3b7..21921f1 100644
--- a/include/efi.h
+++ b/include/efi.h
@@ -278,7 +278,7 @@
 extern char image_base[];
 
 /* Start and end of U-Boot image (for payload) */
-extern char _binary_u_boot_dtb_bin_start[], _binary_u_boot_dtb_bin_end[];
+extern char _binary_u_boot_bin_start[], _binary_u_boot_bin_end[];
 
 /**
  * efi_get_sys_table() - Get access to the main EFI system table