Add in_port_t and move it and in_addr_t to the correct header file.

Add in_port_t and move it and in_addr_t to the correct header file.

No one's reported this, but I saw it in an Android port of fuser(1).

We still have lots of problems in our network headers because we
get most of the structs direct from the kernel, and it doesn't use
types like this (which is why we've got away without this one for
so long). One day we should probably look at cleaning that up, but
doing so can wait.

(cherry picked from commit 35d226e05d92824c6eb992e7a64ea22efc8bae03)

Bug: 18172268
Change-Id: Ice490bfe84afb04722d738128053d4c533b8a664