staging: vc04_services: Avoid NULL comparison

Remove NULL comparison. Issue found using checkpatch.pl

Signed-off-by: Nachammai Karuppiah <nachukannan@gmail.com>
Link: https://lore.kernel.org/r/1570589056-14386-1-git-send-email-nachukannan@gmail.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>