RDMA/siw: Cleanup unused mmap structures.

Removes obsolete driver specific mmap information after
generalization of RDMA driver mmap service. Also removes
useless forward declaration of struct siw_mr.

Fixes: 11f1a755 ("RDMA/siw: Use the common mmap_xa helpers")
Link: https://lore.kernel.org/r/20191113153404.7402-1-bmt@zurich.ibm.comSigned-off-by: Bernard Metzler <bmt@zurich.ibm.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

drivers/infiniband/sw/siw/siw.h

@@ -99,18 +99,9 @@ struct siw_device {
 	struct work_struct netdev_down;
 };
 
-struct siw_uobj {
-	void *addr;
-	u32 size;
-};
-
 struct siw_ucontext {
 	struct ib_ucontext base_ucontext;
 	struct siw_device *sdev;
-
-	/* xarray of user mappable objects */
-	struct xarray xa;
-	u32 uobj_nextkey;
 };
 
 /*
@@ -150,8 +141,6 @@ struct siw_pbl {
 	struct siw_pble pbe[1];
 };
 
-struct siw_mr;
-
 /*
  * Generic memory representation for registered siw memory.
  * Memory lookup always via higher 24 bit of STag (STag index).

drivers/infiniband/sw/siw/siw_verbs.c

@@ -87,8 +87,6 @@ int siw_alloc_ucontext(struct ib_ucontext *base_ctx, struct ib_udata *udata)
 		rv = -ENOMEM;
 		goto err_out;
 	}
-
-	ctx->uobj_nextkey = 0;
 	ctx->sdev = sdev;
 
 	uresp.dev_id = sdev->vendor_part_id;