ARM: bugs: prepare processor bug infrastructure

Prepare the processor bug infrastructure so that it can be expanded to
check for per-processor bugs.

Signed-off-by: Russell King <[e-mail]>
Reviewed-by: Florian Fainelli <[e-mail]>
Boot-tested-by: Tony Lindgren <[e-mail]>
Reviewed-by: Tony Lindgren <[e-mail]>
Acked-by: Marc Zyngier <[e-mail]>

arch/arm/include/asm/bugs.h

···
 #ifndef __ASM_BUGS_H
 #define __ASM_BUGS_H
 
-#ifdef CONFIG_MMU
 extern void check_writebuffer_bugs(void);
 
-#define check_bugs() check_writebuffer_bugs()
+#ifdef CONFIG_MMU
+extern void check_bugs(void);
 #else
 #define check_bugs() do { } while (0)
 #endif

arch/arm/kernel/Makefile

···
 obj-y		+= entry-armv.o
 endif
 
+obj-$(CONFIG_MMU)		+= bugs.o
 obj-$(CONFIG_CPU_IDLE)		+= cpuidle.o
 obj-$(CONFIG_ISA_DMA_API)	+= dma.o
 obj-$(CONFIG_FIQ)		+= fiq.o fiqasm.o

arch/arm/kernel/bugs.c

···
+// SPDX-Identifier: GPL-2.0
+#include <linux/init.h>
+#include <asm/bugs.h>
+#include <asm/proc-fns.h>
+
+void __init check_bugs(void)
+{
+	check_writebuffer_bugs();
+}