If a share type includes the share_backend_name spec,
the scheduler may fail to schedule share replicas unless
all backends in a replication domain share the same
value for the capability "share_backend_name". Having
the same "share_backend_name" isn't desirable all the
time.
Ignore the share_backend_name spec from share type
while creating replica, so the scheduler will filter
a available backend according to the selection policy.
Change-Id: Ic8f7e6230298c222cc6cb5e4e4e8189524aaa81f
Closes-Bug: #1634734
(cherry picked from commit 700c1a02f0)
(cherry picked from commit 19c4869a3f)
(cherry picked from commit e2fe03e253)
(cherry picked from commit bffeef11b4)