Xext: xvmc: drop dead SHM code path

Xvmc isn't using SHM for over 20 years now. There's still a code path for it
that could be enabled explicitly by manually setting HAS_XVMCSHM, but no
indication whatsoever that this ever has been done.

Considering that Xvmc in general already is obsolete for very long time now,
we can safely assume this code path is really dead and can be removed.

Fixes: 9a26d6f39e
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>

Xext/xvmc.c

@@ -24,12 +24,6 @@
 #include "servermd.h"
 #include "xvmcext.h"
 
-#ifdef HAS_XVMCSHM
-#include <sys/ipc.h>
-#include <sys/types.h>
-#include <sys/shm.h>
-#endif                          /* HAS_XVMCSHM */
-
 #define SERVER_XVMC_MAJOR_VERSION               1
 #define SERVER_XVMC_MINOR_VERSION               1
 
@@ -609,10 +603,6 @@ ProcXvMCGetDRInfo(ClientPtr client)
     ScreenPtr pScreen;
     XvMCScreenPtr pScreenPriv;
 
-#ifdef HAS_XVMCSHM
-    volatile CARD32 *patternP;
-#endif
-
     REQUEST(xvmcGetDRInfoReq);
     REQUEST_SIZE_MATCH(xvmcGetDRInfoReq);
 
@@ -641,28 +631,6 @@ ProcXvMCGetDRInfo(ClientPtr client)
      * Read back to the client what she has put in the shared memory
      * segment she prepared for us.
      */
-
-#ifdef HAS_XVMCSHM
-    patternP = (CARD32 *) shmat(stuff->shmKey, NULL, SHM_RDONLY);
-    if (-1 != (long) patternP) {
-        volatile CARD32 *patternC = patternP;
-        int i;
-        CARD32 magic = stuff->magic;
-
-        reply.isLocal = 1;
-        i = 1024 / sizeof(CARD32);
-
-        while (i--) {
-            if (*patternC++ != magic) {
-                reply.isLocal = 0;
-                break;
-            }
-            magic = ~magic;
-        }
-        shmdt((char *) patternP);
-    }
-#endif                          /* HAS_XVMCSHM */
-
     if (client->swapped) {
         swapl(&reply.major);
         swapl(&reply.minor);