Staging: xgifb: Fix comparison to NULL warning

Change comparison to NULL to a ! operation.
Found using checkpatch.

Signed-off-by: Navya Sri Nizamkari <navyasri.tech@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Navya Sri Nizamkari 2015-10-22 22:18:26 +05:30 • committed by Greg Kroah-Hartman
commit 076e235856