[PATCH] USB: Fix race condition in usblp_write

Initialize status fields in the read and write urbs to prevent a race
condition with open/read/close - open/write/close sequences.

Fixes bug #4432 at bugzilla.kernel.org

Signed-off-by: Adam Oldham <oldhamca@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>