checkpatch: cache last camelcase hash as .checkpatch-camelcase.<commit>
checkpatch: cache last camelcase hash as .checkpatch-camelcase.<commit>

Add a file to cache the CamelCase variables found by <commit> to reduce
the time it takes to scan the include/ directory.

Filename is '.checkpatch-camelcase.<commit>' and it is created only only
if a .git directory exists.

<commit> is determined by the last non-merge commit id in the
include/ path.

Reduces checkpatch run time by ~12 cpu seconds on my little netbook.

Signed-off-by: Joe Perches <16a9a54ddf4259952e3c118c763138e83693d7fd@perches.com>
Signed-off-by: Andrew Morton <5c1e68b099950c134891f0b6e179498a8ebe9cf9@linux-foundation.org>
Signed-off-by: Linus Torvalds <69652caca27c8b940640ad396ab71f93cacec34f@linux-foundation.org>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs