MFC r333121, r333128

r333121:
cxgbe/t4_tom: Use appropriate macros instead of magic math while
constructing the atid of an active open work request.

Sponsored by: Chelsio Communications

r333128:
cxgbe(4): Convert ACT_OPEN_RPL to a shared CPL.

Reserve 3b in the 14b atid to identify the owner and use it to dispatch
the CPL. This allows all CPLs that use an atid to be used as shared
CPLs, although ACT_OPEN_RPL is the only one being converted in this
revision.

Sponsored by: Chelsio Communications