IB/hfi1: Clean up context initialization

Context initialization mixes base context init with sub context init.
This is bad because contexts can be reused, and on reuse, reinit things
that should not re-initialized.

Normalize comments and function names to refer to base context and
sub context (not main, shared or slaves).

Separate the base context initialization from sub context initialization.

hfi1_init_ctxt() cannot return an error so changed to a void and remove
error message.

Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>