IB/rdmavt: Add protection domain to rdmavt.

Add datastructure for and allocation/deallocation of protection domains for
RDMAVT.

Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

drivers/infiniband/sw/rdmavt/vt.h

@@ -50,5 +50,6 @@
 
 #include <rdma/rdma_vt.h>
 #include "dma.h"
+#include "pd.h"
 
 #endif          /* DEF_RDMAVT_H */