usb: serial: fix memory leak in generic driver
usb: serial: fix memory leak in generic driver

Fix a regression introduced by commit
715b1dc01fe44537e8fce9566e4bb48d6821d84b ("USB: usb_debug,
usb_generic_serial: implement multi urb write").

URB transfer buffer was never freed when using multi-urb writes. 
Currently the only driver enabling multi-urb writes is usb_debug.

Signed-off-by: Johan Hovold <6a430eed381e126d51a8cce8db662f765ce314bc@gmail.com>
Cc: Greg KH <79e2475f81a6317276bf7cbb3958b20d289b78df@kroah.com>
Acked-by: Jason Wessel <3f19c87103ac4cd0301ffd05a2421b687c7b3c77@windriver.com>
Cc: stable <4fbacc2fa0ffdbb11bf1ad6925b886ebd08dd15f@kernel.org>
Signed-off-by: Andrew Morton <5c1e68b099950c134891f0b6e179498a8ebe9cf9@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <4645f7897fd33786a2ee1264d590b3c400559d85@suse.de>


KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs