USB: mdm_bridge: Simplify data bridge suspend/resume path

Synchronous runtime PM API is used to increment the PM usage counter
in Tx path.  It means Tx data path will not race with interface suspend.
Remove "delayed" anchor which is meant for Tx requests, that are arrived
during suspend.  There is no point in distinguishing auto suspend and
system wide suspend.  Abort suspend when we have pending Tx URBs.

CRs-Fixed: 451414
Change-Id: I302b120ccecfe30db1ebd2b1fcd9945a3675cf83
Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.org>