usb: gadget: fix USBCV - Chapter 9 test failure

Failed test "Halt Endpoint". The reasons for failure were
reconnecting the bam2bam at set_alt and fauilre to halt
endless transfer.No reconnecting of bam2bam will take
place on set_alt or set_halt.

CRs-Fixed: 344801
Change-Id: I027676bb8d98d20cf0b6c82c688ac9e36dcbfe64
Signed-off-by: Bar Weiner <bweiner@codeaurora.org>

Conflicts:

	drivers/usb/gadget/f_rmnet.c