checkpatch: check for #if 0/#if 1

Warn if #if 1 or #if 0 is present.

Signed-off-by: Abhijeet Dharmapurikar <adharmap@codeaurora.org>
(cherry picked from commit a81f92c9abe442ad5b00e8df31172f145a14af3f)
Signed-off-by: Stepan Moskovchenko <stepanm@codeaurora.org>
Signed-off-by: Rishabh Bhatnagar <rishabhb@codeaurora.org>

Change-Id: I91eeb530c08815324af69df8c12f7ece3fd0378c