OSHMEM: sshmem verbs: improve hca name parsing

If user gives hca port ignore port, use only hca name.
Ex: mlx4_0:1 -> mlx4_0

fixed by @alex-mikheev reviewed by @miked-mellanox
(cherry picked from commit 4ac59362577ef0f48741663281c9caef7f1357a8)
OSHMEM: sshmem verbs: allocate memory at fixed address

Use experimental verbs to allocate memory at fixed base
virtual address.

verbs will disqualify itself if shared_mr is disabled
or not supported and it is impossible to allocate memory
starting at fixed base virtual address.

verbs contig pages allocator did not guarantee fixed va, now it does.
(cherry picked from commit fd77ebd4525e9e0c1a3ab1c4966bf31aa45251b4)

Update with Jeff commits
Merge branch 'topic/fix-verbs-allocator-to-use-fixed-va' of https://github.com/miked-mellanox/ompi-release into topic/fix-verbs-allocator-to-use-fixed-va