checkpatch: remove quote from CamelCase test

Commit be987d9f ("checkpatch: improve CamelCase test for Page") added
it but it shouldn't be there.  Must have been my fault.

Make sure that the tested variable doesn't contain a constant.

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>