usb/gadget: free opts struct on error recovery

usb/gadget: free opts struct on error recovery

Fix memory leaks introduced in commits:

c7370bc15057c5ffea3fe7d04de86677315b14b2
usb: gadget: f_ncm: convert to new function interface with backward compatibility

8e14606d2228c05796eb23e695ad3046b8e654d0
usb: gadget: f_ecm: convert to new function interface with backward compatibility

398807f0ddd972d87442bbb6d577859fdfb40525
usb: gadget: f_phonet: convert to new function interface with backward compatibility

8c0da1ba7f2adf863b9d56e13d12875abca7df4e
usb: gadget: f_eem: convert to new function interface with backward compatibility

570f292b6e41408bc44cb772c0354eafb0b9ab41
usb: gadget: f_subset: convert to new function interface with backward compatibility

e007d00ee206bde0f83ea76f789143531387c0be
usb: gadget: f_rndis: convert to new function interface with backward compatibility

Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>