lockdep: Provide off case for redundant_hardirqs_on increment

We forgot to provide a !CONFIG_DEBUG_LOCKDEP case for the
redundant_hardirqs_on stat handling.

Manage that in the headers with a new __debug_atomic_inc() helper.

Fixes:

	kernel/lockdep.c:2306: error: 'lockdep_stats' undeclared (first use in this function)
	kernel/lockdep.c:2306: error: (Each undeclared identifier is reported only once
	kernel/lockdep.c:2306: error: for each function it appears in.)
Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>

kernel/lockdep.c

@@ -2303,7 +2303,7 @@ void trace_hardirqs_on_caller(unsigned long ip)
 		 * so this is racy by nature but loosing one hit
 		 * in a stat is not a big deal.
 		 */
-		this_cpu_inc(lockdep_stats.redundant_hardirqs_on);
+		__debug_atomic_inc(redundant_hardirqs_on);
 		return;
 	}
 	/* we'll do an OFF -> ON transition: */

kernel/lockdep_internals.h

@@ -139,6 +139,9 @@ struct lockdep_stats {
 
 DECLARE_PER_CPU(struct lockdep_stats, lockdep_stats);
 
+#define __debug_atomic_inc(ptr)					\
+	this_cpu_inc(lockdep_stats.ptr);
+
 #define debug_atomic_inc(ptr)			{		\
 	WARN_ON_ONCE(!irqs_disabled());				\
 	this_cpu_inc(lockdep_stats.ptr);			\
@@ -160,6 +163,7 @@ DECLARE_PER_CPU(struct lockdep_stats, lockdep_stats);
 	__total;							\
 })
 #else
+# define __debug_atomic_inc(ptr)	do { } while (0)
 # define debug_atomic_inc(ptr)		do { } while (0)
 # define debug_atomic_dec(ptr)		do { } while (0)
 # define debug_atomic_read(ptr)		0