usb: gadget: core: Fix use-after-free of usb_request

[ Upstream commit e74bd4d358e5455233f1dcc3975425905b270b91 ]

Driver is tracing usb_request after freeing it.
Fix it by changing the order.

Signed-off-by: Manu Gautam <mgautam@codeaurora.org>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>