staging: wlan-ng: fix NULL comparison

Fix NULL equality comparision by changing it with exclamation mark,
as suggested by Documentation/CodingStyle

Signed-off-by: Fu Yong Quah <fuyong@linux.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Fu Yong Quah 2016-02-20 10:23:14 +00:00 • committed by Greg Kroah-Hartman
commit 1e613801ce