sh: Generic HAVE_PERF_COUNTER support.

This enables support for the generic software-based perf counters.

Hardware counter support could be added in the future, but the lack
of a performance counter IRQ makes this rather dubious.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

arch/sh/Kconfig

@@ -15,6 +15,7 @@ config SUPERH
 	select HAVE_IOREMAP_PROT if MMU
 	select HAVE_ARCH_TRACEHOOK
 	select HAVE_DMA_API_DEBUG
+	select HAVE_PERF_COUNTER
 	select RTC_LIB
 	select GENERIC_ATOMIC64
 	help

arch/sh/include/asm/perf_counter.h

+#ifndef __ASM_SH_PERF_COUNTER_H
+#define __ASM_SH_PERF_COUNTER_H
+
+/* SH only supports software counters through this interface. */
+#define set_perf_counter_pending()	do { } while (0)
+
+#endif /* __ASM_SH_PERF_COUNTER_H */