staging: usbip: userspace: libsrc: do not init static/globals to 0

This patch fixes the following checkpatch errors:
-ERROR: do not initialise statics to 0 or NULL
-ERROR: do not initialise globals to 0 or NULL

Signed-off-by: Kurt Kanzenbach <ly80toro@cip.cs.fau.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>