4.26: mpeg link errors version 2.0

From: Nathan Lane <nathan@seldon.foundation.tricon.com>

.XShmCreateImage
.XShmDetach
.XShmAttach
.XShmGetEventBase
.XShmPutImage
.XShmQueryExtension

... are for the Shared Memory extension of the X server.
You can either choose to build it with shared memory or without.  I
always do it without the performance increase is not really
incredible, except on something like a 2x0 machine with the local bus
graphics adapter.  Just take out "DSH_MEM" in the CFLAGS in the
makefile for mpeg_play.  There is more information about shared memory
link errors in section 1.513.

Also, in the module "video.c" for mpeg_play it will complain about not
having enough memory to fully optimize one of the loops.  You can get
around that by specificying "qmaxmem=8000" in your cflags line, BUT,
the extra optimization does little good in my tests.