NFSv4 handle port presence in fs_location server string

[ Upstream commit a8d54bab ]

An fs_location attribute returns a string that can be ipv4, ipv6,
or DNS name. An ip location can have a port appended to it and if
no port is present a default port needs to be set. If rpc_pton()
fails to parse, try calling rpc_uaddr2socaddr() that can convert
an universal address.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>