SUNRPC: Fix a few sparse warnings

net/sunrpc/svcsock.c:412:22: warning: incorrect type in assignment
(different address spaces)
 - svc_partial_recvfrom now takes a struct kvec, so the variable
   save_iovbase needs to be an ordinary (void *)

Make a bunch of variables in net/sunrpc/xprtsock.c static

Fix a couple of "warning: symbol 'foo' was not declared. Should it be
static?" reports.

Fix a couple of conflicting function declarations.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

net/sunrpc/backchannel_rqst.c

@@ -25,6 +25,7 @@ SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #include <linux/slab.h>
 #include <linux/sunrpc/xprt.h>
 #include <linux/export.h>
+#include <linux/sunrpc/bc_xprt.h>
 
 #ifdef RPC_DEBUG
 #define RPCDBG_FACILITY	RPCDBG_TRANS