arm64: enable KEXEC_FILE config

Modify arm64/Kconfig to enable kexec_file_load support.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Acked-by: James Morse <james.morse@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

arch/arm64/kernel/machine_kexec_file.c

@@ -0,0 +1,16 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * kexec_file for arm64
+ *
+ * Copyright (C) 2018 Linaro Limited
+ * Author: AKASHI Takahiro <takahiro.akashi@linaro.org>
+ *
+ */
+
+#define pr_fmt(fmt) "kexec_file: " fmt
+
+#include <linux/kexec.h>
+
+const struct kexec_file_ops * const kexec_file_loaders[] = {
+	NULL
+};