neard: fix build with kernel headers 3.1 - 3.6

neard uses the linux/nfc.h header which is fairly recent, so we have a
patch that creates linux-nfc.h and uses it if necessary. However, since
the bump to 0.9, neard uses some symbols that are introduced in linux 3.7
so the build fails with headers 3.1 (which introduced nfc.h) to 3.6.

To resolve that, add a check for one of the newly introduced symbols
(that is used by neard).

Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>