scripts/checkpatch.pl: add WARN on sizeof(&foo)

sizeof(&foo) is frequently an error.  Warn on its use.
Signed-off-by: NJoe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

scripts/checkpatch.pl

@@ -2572,6 +2572,11 @@ sub process {
 			WARN("plain inline is preferred over $1\n" . $herecurr);
 		}
 
+# check for sizeof(&)
+		if ($line =~ /\bsizeof\s*\(\s*\&/) {
+			WARN("sizeof(& should be avoided\n" . $herecurr);
+		}
+
 # check for new externs in .c files.
 		if ($realfile =~ /\.c$/ && defined $stat &&
 		    $stat =~ /^.\s*(?:extern\s+)?$Type\s+($Ident)(\s*)\(/s)