checkpatch: prefer dev_<level>( to dev_printk(KERN_<LEVEL>

Add YA check to printk style.

dev_<level> uses are functions and generate smaller
object code than dev_printk(KERN_<LEVEL>.
Signed-off-by: NJoe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

scripts/checkpatch.pl

@@ -2430,6 +2430,15 @@ sub process {
 			     "Prefer pr_warn(... to pr_warning(...\n" . $herecurr);
 		}
 
+		if ($line =~ /\bdev_printk\s*\(\s*KERN_([A-Z]+)/) {
+			my $orig = $1;
+			my $level = lc($orig);
+			$level = "warn" if ($level eq "warning");
+			$level = "dbg" if ($level eq "debug");
+			WARN("PREFER_DEV_LEVEL",
+			     "Prefer dev_$level(... to dev_printk(KERN_$orig, ...\n" . $herecurr);
+		}
+
 # function brace can't be on same line, except for #defines of do while,
 # or if closed on same line
 		if (($line=~/$Type\s*$Ident\(.*\).*\s{/) and