fix WARN() for PPC

powerpc doesn't use the generic WARN_ON infrastructure.  The newly
introduced WARN() as a result didn't print the message, this patch adds
the printk for this specific case.
Signed-off-by: NArjan van de Ven <arjan@linux.intel.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

include/asm-generic/bug.h

@@ -41,7 +41,7 @@ extern void warn_slowpath(const char *file, const int line,
 #define __WARN() warn_on_slowpath(__FILE__, __LINE__)
 #define __WARN_printf(arg...) warn_slowpath(__FILE__, __LINE__, arg)
 #else
-#define __WARN_printf(arg...) __WARN()
+#define __WARN_printf(arg...) do { printk(arg); __WARN(); } while (0)
 #endif
 
 #ifndef WARN_ON