Move everything to where it should be.
Along the way, we lose <net/ethertypes.h>. glibc only has a handful of these
types, and they're all in <net/ethernet.h>, not <net/ethertypes.h>. I've taken
the liberty of not including the AppleTalk ones, since it is 2016.
Also, <net/if_ether.h> should be <netinet/if_ether.h> (though with different
contents).
Bug: http://b/28519060
Change-Id: Ia41c3fc136fd3e6b008c8d08018e0629134ea6fc
I'll need at least one more pass, because there's some upstream code
lurking in libc/bionic, but this is still a step in the right direction.
Change-Id: I55927315972da8327ae01c5240ed587db17e8462