[PATCH] trace: Fix build breakage without CONFIG_PERF_EVENTS

[Mark Brown <broonie@opensource.wolfsonmicro.com>]

Today's -next fails to build for me:

  CC      kernel/trace/trace_export.o
In file included from kernel/trace/trace_export.c:197: kernel/trace/trace_entries.h:58: error: 'perf_ftrace_event_register' undeclared here (not in a function)
make[2]: *** [kernel/trace/trace_export.o] Error 1
make[1]: *** [kernel/trace] Error 2
make: *** [kernel] Error 2

because as of ced390 (ftrace, perf: Add support to use function
tracepoint in perf) perf_trace_event_register() is declared in trace.h
only if CONFIG_PERF_EVENTS is enabled but I don't have that set.

Ensure that we always have a definition of perf_trace_event_register()
by making the definition unconditional.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
---
 kernel/trace/trace.h |    2 --
 1 files changed, 0 insertions(+), 2 deletions(-)

diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 54faec7..3dd357c 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -835,13 +835,11 @@ extern const char *__stop___trace_bprintk_fmt[];
 		     filter)
 #include "trace_entries.h"
 
-#ifdef CONFIG_PERF_EVENTS
 #ifdef CONFIG_FUNCTION_TRACER
 int perf_ftrace_event_register(struct ftrace_event_call *call,
 			       enum trace_reg type, void *data);
 #else
 #define perf_ftrace_event_register NULL
 #endif /* CONFIG_FUNCTION_TRACER */
-#endif /* CONFIG_PERF_EVENTS */
 
 #endif /* _LINUX_KERNEL_TRACE_H */
-- 
1.7.9.1