checkpatch: allow longer logging function names

The current $logFunction regular expression allows names like dev_warn,
e_dbg, netdev_info, etc, but some log functions are now written like
e_dev_warn, so allow 1 or 2 word blocks with an underscore before the
logging level.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 70e7f7c..0d94853 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -281,7 +281,7 @@
 
 our $logFunctions = qr{(?x:
 	printk(?:_ratelimited|_once|)|
-	[a-z0-9]+_(?:printk|emerg|alert|crit|err|warning|warn|notice|info|debug|dbg|vdbg|devel|cont|WARN)(?:_ratelimited|_once|)|
+	(?:[a-z0-9]+_){1,2}(?:printk|emerg|alert|crit|err|warning|warn|notice|info|debug|dbg|vdbg|devel|cont|WARN)(?:_ratelimited|_once|)|
 	WARN(?:_RATELIMIT|_ONCE|)|
 	panic|
 	MODULE_[A-Z_]+