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
Note that the Linux kernel handed over responsibility for most of the
socket constants to glibc some time ago. Someone had updated our
external/kernel-headers file but not regenerated the bionic headers,
so this change copies the missing stuff from the old bionic <linux/socket.h>
into <sys/socket.h>. This is what glibc does.
I've hacked a few of the other files to #include <sys/socket.h> for
backward compatibility, but even so this requires numerous other
changes to switch people over from direct inclusion of <linux/...> headers.
Change-Id: I0e4af64e631d3cef911a31d90f2f806e058278a0
