ofed/infiniband: fix ifdefs for new INET changes, fixing LINT-NOIP

Some of the ofed/infiniband code has INET and INET6 address handling
code without using ifdefs. This failed with a recent change to INET,
in which IN_LOOPBACK() started using a VNET variable, and which is not
present if INET is not configured. Add #ifdef INET, and INET6 for good
measure, in cma_loopback_addr(), along with inclusion of the options
headers in ib_cma.c.

Reviewed by: hselasky rgrimes bz
Differential Revision: https://reviews.freebsd.org/D35835

(cherry picked from commit 752b7632776237f9c071783acdd1136ebf5f287d)