Remove __qaddr_t.

bits/types.h defines a type __qaddr_t that is not used anywhere in
glibc.  It doesn't appear to be widely used outside glibc either
(judging by codesearch.debian.net, where hits are generally copies of
definitions of this type, not uses), so it seems appropriate to remove
this type, which this patch does.

Tested for x86_64.

	* posix/bits/types.h (__qaddr_t): Remove.