datapath: Change vals[] in struct port_lookup_key into discrete members.

datapath: Change vals[] in struct port_lookup_key into discrete members.

The 'vals' array is only convenient for use by port_hash().  It's a
liability otherwise, since it makes the code wider and harder to read and
seems to me less amenable to compiler optimization.

In an upcoming patch the key needed in struct port_lookup_key will
increase in size to 64 bits, so that using an array of u32 becomes even
more problematic.  Therefore, this commit gets rid of the array in favor
of discrete named members that carry the same information.

Signed-off-by: Ben Pfaff <blp@nicira.com>
Acked-by: Jesse Gross <jesse@nicira.com>