usb: gadget: fsl_udc_core: check allocation return value and cleanup on failure

usb: gadget: fsl_udc_core: check allocation return value and cleanup on failure

The allocation with fsl_alloc_request() and kmalloc() were unchecked
fixed this up with a NULL check and appropriate cleanup.

Additionally udc->ep_qh_size was reset to 0 on failure of allocation.
Similar udc->phy_mode is initially 0 (as udc_controller was
allocated with kzalloc in fsl_udc_probe()) so reset it to 0 as well
so that this function is side-effect free on failure. Not clear if
this is necessary or sensible as fsl_udc_release() probably can not
be called if fsl_udc_probe() failed - but it should not hurt.

Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Fixes: b504882da5 ("USB: add Freescale high-speed USB SOC device controller driver")
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>