checkpatch: don't warn on blank lines before/after braces as often

Check to make sure the blank lines aren't comment lines like:

  bool foo(bool bar)
  {
	/* Don't warn on a leading comment */
	return !bar;
	/* Don't warn on a trailing comment either */
  }

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>