usb: musb: core: fix failure path

In the fail1~fail5 failure path, pm_runtime_disable() should
be called to avoid 'Unbalanced pm_runtime_enable' error in
next probe() which may be triggered by defer probe or next
'modprobe musb_hdrc'.

Cc: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Cc: <stable@vger.kernel.org> v3.8
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>