USB: u_data_ipa: Fix pm_runtime_get/put() mismatch

If IPA driver is disabled or IPA driver can fail when tether_bridge_init()
is called as part of connect_work. In this case, as part of connect_work,
results in not decrementing pm_usage counter, which causes USB not
entering low power mode. Fix the issue by decrementing pm_usage counter
in error cases.

Change-Id: I7fdb7a28e3e2da6d4c0b01e69e3551f81d000aa4
Signed-off-by: Vijayavardhan Vennapusa <vvreddy@codeaurora.org>