xprtrdma: Clean up device capability detection

Clean up: Move device capability detection into memreg-specific
source files.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

net/sunrpc/xprtrdma/xprt_rdma.h

@@ -446,6 +446,8 @@ extern int xprt_rdma_pad_optimize;
  */
 int rpcrdma_ia_open(struct rpcrdma_xprt *, struct sockaddr *, int);
 void rpcrdma_ia_close(struct rpcrdma_ia *);
+bool frwr_is_supported(struct rpcrdma_ia *);
+bool fmr_is_supported(struct rpcrdma_ia *);
 
 /*
  * Endpoint calls - xprtrdma/verbs.c