Log Message:
Update to xextproto-7.1.1.

"Many headers included in xextproto were combined library, server and
 protocol headers. This release splits those headers up and moves the
 client-side library headers into the libXext module.
 Clients should not be affected by this change.
 Drivers that included headers from this module will need to be fixed."

"Note that as a result of this file removal and renaming, xextproto is only
 partially compatible to other, already released modules. An upgrade of
 xextproto from 7.0.x to 7.1.0 also requires upgrades of libXext, libXtst,
 the X server and possible others."

xxx tnn note: I've added a compat shmstr.h to help old software,
such as xorg-server 1.6 to build. More fixes coming.