checkpatch: add DT compatible string documentation checks
checkpatch: add DT compatible string documentation checks

This adds a simple check that any compatible strings in DeviceTree dts
files are present in Documentation/devicetree/bindings.  Vendor prefixes
are also checked for existing in vendor-prefixes.txt These should be
temporary checks until we have more sophisticated binding schema
checking.

Signed-off-by: Rob Herring <fbb37eacae100e13076d5c4b46f06cfa4d6fa9f8@kernel.org>
Signed-off-by: Joe Perches <16a9a54ddf4259952e3c118c763138e83693d7fd@perches.com>
Cc: Grant Likely <9069e6f5a2b566e2674a0ba1e2bf39c12c195fad@linaro.org>
Cc: Andy Whitcroft <b4658fdd7fbd645c2859b0e39d71018f32058d12@canonical.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