[SUNRPC]: Make xprtsock.c:xs_setup_{udp,tcp}() static

xs_setup_{udp,tcp}() can now become static.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>