IB/hfi1: Fix dc8051 multiple qword memory reads

When reading multiple dc8051 data memory locations
at once, the read enabled field must be toggled
at every address change.  Do that by writing only
the address first, then writing the enable.

Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Dean Luick <dean.luick@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>