USB: ci13xxx: Drop spin_lock before notifying CONNECT to udc driver

Some UDC drivers e.g. HSIC manage their runtime PM themselves. This
can result in udc driver to perform runtime resume on CONNECT
notification. Hence, drop spin_lock before notifying CONNECT to
allow HSIC UDC driver to bring HSIC device out of LPM and
continue to ignore children for power management.

Change-Id: Ia5ba943b4ddad7448cc6b94f28f47a68d6b2ac33
Signed-off-by: Manu Gautam <mgautam@codeaurora.org>