usb: gadget: f_rndis: Avoid to use ERROR macro if cdev can be null
usb: gadget: f_rndis: Avoid to use ERROR macro if cdev can be null

The udc_irq service runs the isr_tr_complete_handler which in turn
"nukes" the endpoints, including a call to rndis_response_complete,
if appropriate. If the rndis_msg_parser fails here, an error will
be printed using a dev_err call (through the ERROR() macro).

However, if the usb cable was just disconnected the device (cdev)
might not be available and will be null. Since the dev_err macro will
dereference the cdev pointer we get a null pointer exception.

Reviewed-by: Radovan Lekanovic <2adbf03b8496779b7bc35b28efcef6f339f9a036@sonymobile.com>
Signed-off-by: Truls Bengtsson <9dafe0a846d60b30be9cc1704a9f2897a5696ed5@sonymobile.com>
Signed-off-by: Oskar Andero <c9df5aae2ef47fc44b10c327f669dac43c6c849c@sonymobile.com>
Acked-by: Michal Nazarewicz <605208d9b4c769ca62e9f9f8b592c9cd465fe6d7@mina86.com>
Signed-off-by: Felipe Balbi <94dddeeef08b001e003cce128ddc162a4e2c6cd2@ti.com>

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