microblaze: Define microblaze barrier

Define microblaze barrier.
Signed-off-by: Stefan Asserhall <stefan.asserhall@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>

arch/microblaze/include/asm/Kbuild

 # SPDX-License-Identifier: GPL-2.0
 generated-y += syscall_table.h
-generic-y += barrier.h
 generic-y += bitops.h
 generic-y += bug.h
 generic-y += bugs.h

arch/microblaze/include/asm/barrier.h

+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2015 - 2020 Xilinx, Inc. All rights reserved.
+ */
+
+#ifndef _ASM_MICROBLAZE_BARRIER_H
+#define _ASM_MICROBLAZE_BARRIER_H
+
+#define mb()	__asm__ __volatile__ ("mbar 1" : : : "memory")
+
+#include <asm-generic/barrier.h>
+
+#endif /* _ASM_MICROBLAZE_BARRIER_H */