hw-breakpoints: Fix misordered ifdef

Fix a misplaced ifdef. We need the perf event headers also in
off-case to avoid the following build error:

 include/linux/hw_breakpoint.h:94: error: expected declaration specifiers or '...' before 'perf_callback_t'
 include/linux/hw_breakpoint.h:102: error: expected declaration specifiers or '...' before 'perf_callback_t'
 include/linux/hw_breakpoint.h:109: error: expected declaration specifiers or '...' before 'perf_callback_t'
 include/linux/hw_breakpoint.h:116: error: expected declaration specifiers or '...' before 'perf_callback_t'

Reported-by: Kisskb-bot by Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Prasad <prasad@linux.vnet.ibm.com>
LKML-Reference: <1259011812-8093-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

include/linux/hw_breakpoint.h

@@ -15,10 +15,11 @@ enum {
 };
 
 #ifdef __KERNEL__
-#ifdef CONFIG_HAVE_HW_BREAKPOINT
 
 #include <linux/perf_event.h>
 
+#ifdef CONFIG_HAVE_HW_BREAKPOINT
+
 static inline unsigned long hw_breakpoint_addr(struct perf_event *bp)
 {
 	return bp->attr.bp_addr;