ARM: move CP15 definitions to separate header file

Avoid namespace conflicts with drivers over the CP15 definitions by
moving CP15 related prototypes and definitions to a private header
file.

Acked-by: Stephen Warren <swarren@nvidia.com>
Tested-by: Stephen Warren <swarren@nvidia.com> [Tegra]
Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Tested-by: H Hartley Sweeten <hsweeten@visionengravers.com> [EP93xx]
Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>

arch/arm/mm/cache-xsc3l2.c

@@ -18,7 +18,7 @@
  */
 #include <linux/init.h>
 #include <linux/highmem.h>
-#include <asm/system.h>
+#include <asm/cp15.h>
 #include <asm/cputype.h>
 #include <asm/cacheflush.h>