checkpatch: toughen trailing if statement checks and extend them to while and for

Extend the trailing statement checks to report a trailing semi-colon ';'
as we really want it on the next line and indented so it is really really
obvious.  Also extend the tests to include while and for.

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