Show endpoint direction based on EPHandle bit

Interpret the meaning of the endpoint handle direction bit,
instead of just saying if it is set.

Change-Id: I9fc0d6f95f6c3a94d6db90c8394fe3ca8fc83715
Reviewed-on: https://code.wireshark.org/review/4119
Reviewed-by: Evan Huus <eapache@gmail.com>