staging: dgap: fix possible NULL dereference
staging: dgap: fix possible NULL dereference

The return pointer from dgap_getword() is used in strcmp() where it is
dereferenced. But dgap_getword() can return NULL.
Lets put a check there and return 0 as error.

Signed-off-by: Sudip Mukherjee <8ebcb270388efeefbc3b674e2d51f150dd6e6b25@vectorindia.org>
Signed-off-by: Greg Kroah-Hartman <4645f7897fd33786a2ee1264d590b3c400559d85@linuxfoundation.org>

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