packet-infiniband: Fixed displaying reserved field

packet-infiniband: Fixed displaying reserved field

1. Added Extended transport type field instead of reserved as per latest
release 1.3.1 in CM Req msg.
2. Defined reserved bits and bytes for CM messages
3. Minor code refactor to move to smaller functions for CM Req Rsp
parsing instead of 200+ lines function which is hard to read and
is expected to grow for more features
4. Cleanup around primary and alternate fields which were crossing byte
boundary

CM request and response messages are tested.
Reject message reserved fields change is untested but it a minor change
that is expected to work.

Change-Id: I94da62614f854218249b4e14c780f4168f44751c
Reported-by: Alexis La Goutte
Tested-by: paravpandit@yahoo.com
Reviewed-on: https://code.wireshark.org/review/18340
Petri-Dish: Michael Mann <mmann78@netscape.net>
Tested-by: Petri Dish Buildbot <buildbot-no-reply@wireshark.org>
Petri-Dish: Alexis La Goutte <alexis.lagoutte@gmail.com>
Reviewed-by: Alexis La Goutte <alexis.lagoutte@gmail.com>
Reviewed-by: Jaap Keuter <jaap.keuter@xs4all.nl>