checkpatch: correctly stop scanning at the bottom of a hunk

We are allowing context scanning checks to apply against the first line of
context outside at the end of the hunk.  This can lead to false matches to
patch names leading to various perl warnings.  Correctly stop at the
bottom of the hunk.

Signed-off-by: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>