x86: efi: Add EFI loader support for x86

Add the required pieces to support the EFI loader on x86.

Since U-Boot only builds for 32-bit on x86, only a 32-bit EFI application
is supported. If a 64-bit kernel must be booted, U-Boot supports this
directly using FIT (see doc/uImage.FIT/kernel.its). U-Boot can act as a
payload for both 32-bit and 64-bit EFI.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
diff --git a/lib/efi_loader/efi_runtime.c b/lib/efi_loader/efi_runtime.c
index f73e6d9..f007ca6 100644
--- a/lib/efi_loader/efi_runtime.c
+++ b/lib/efi_loader/efi_runtime.c
@@ -44,6 +44,10 @@
 #elif defined(CONFIG_ARM)
 #define R_RELATIVE	23
 #define R_MASK		0xffULL
+#elif defined(CONFIG_X86)
+#include <asm/elf.h>
+#define R_RELATIVE	R_386_RELATIVE
+#define R_MASK		0xffULL
 #else
 #error Need to add relocation awareness
 #endif