IB/mthca: Factor out setting WQE data segment entries
Factor code to set data segment entries out of the work request
posting functions into inline functions mthca_set_data_seg() and
mthca_set_data_seg_inval(). This makes the code more readable and
also allows the compiler to do a better job -- on x86_64:
add/remove: 0/0 grow/shrink: 0/6 up/down: 0/-69 (-69)
function old new delta
mthca_arbel_post_srq_recv 373 369 -4
mthca_arbel_post_receive 570 562 -8
mthca_tavor_post_srq_recv 520 508 -12
mthca_tavor_post_send 1344 1330 -14
mthca_arbel_post_send 1481 1467 -14
mthca_tavor_post_receive 792 775 -17
Signed-off-by: Roland Dreier <rolandd@cisco.com>