staging: keucr: remove needless check before usb_free_coherent()
staging: keucr: remove needless check before usb_free_coherent()

usb_free_coherent() is safe with NULL addr and this check is
not required.

Signed-off-by: Wei Yongjun <b8f9cab8be13de37b9588aedad10a20fc3a68783@trendmicro.com.cn>
Signed-off-by: Greg Kroah-Hartman <4645f7897fd33786a2ee1264d590b3c400559d85@linuxfoundation.org>

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