usb: gadget: fotg210-udc: Fix memory leak of fotg210->ep[i]

[ Upstream commit c37bd52836296ecc9a0fc8060b819089aebdbcde ]

There is no deallocation of fotg210->ep[i] elements, allocated at
fotg210_udc_probe.

The patch adds deallocation of fotg210->ep array elements and simplifies
error path of fotg210_udc_probe().

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Anton Vasilyev <vasilyev@ispras.ru>
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>