Fix SI95 transport header length bug

A bug in the buffer length extraction from the SI95 transport
header was causing failures when communicating with an application
using a backlevel version of RMR.  Symptoms were dropped return
to sender messages, and a flood of messages with type 0.  This
fix corrects this problem.

Issue-ID: RIC-341

Signed-off-by: E. Scott Daniels <daniels@research.att.com>
Change-Id: I0223608c26917a5f94378fd83e1bb71be93999fe
4 files changed