Staging: crystalhd: remove an unneeded NULL check

We already established earlier in the function that "temp" is
non-NULL.  We also don't need to set to NULL because it's a stack
variable an we return immediately.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>