usb: gadget: phonet: free requests in pn_bind()'s error path

commit d0eca719dd11ad0619e8dd6a1f3eceb95b0216dd upstream.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>