Disintegrate asm/system.h for Sparc

Disintegrate asm/system.h for Sparc.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: sparclinux@vger.kernel.org
diff --git a/arch/sparc/kernel/nmi.c b/arch/sparc/kernel/nmi.c
index c76fe0b..eb1c1f0 100644
--- a/arch/sparc/kernel/nmi.c
+++ b/arch/sparc/kernel/nmi.c
@@ -22,6 +22,7 @@
 #include <asm/perf_event.h>
 #include <asm/ptrace.h>
 #include <asm/pcr.h>
+#include <asm/perfctr.h>
 
 #include "kstack.h"