staging/lustre/o2iblnd: remove references to ib_reg_phsy_mr()

Removed references to ib_reg_phsy_mr() and PMR which was added
to deal with some Chelsio specific scenario, but no longer needed
now.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Amir Shehata <amir.shehata@intel.com>
Signed-off-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>