checkpatch: create an EXPERIMENTAL --fix option to correct patches

Some patches have simple defects in whitespace and formatting that
checkpatch could correct automatically.  Attempt to do so.

Add a --fix option to create a "<inputfile>.EXPERIMENTAL-checkpatch-fixes"
file that tries to use normal kernel style for some of these formatting
errors.

Add warnings against using this file without verifying the changes.

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>