XvMC allocation fixes

From: Daniel Drake <dsd@gentoo.org>

Users at https://bugs.gentoo.org/show_bug.cgi?id=228473 report problems using
software such as MythTV:

ViaXvMC: Could not allocate timestamp blit area.
2008-06-20 11:25:39.231 VideoOutputXv Error: Unable to create XvMC Context, status(11): BadAlloc
2008-06-20 11:25:39.233 VideoOutputXv Error: Could not open XvMC port...

We tracked this down to a bug in the libxvmc code, which does not
pass the right structure size to the ioctl: it calls sizeof() on a pointer
I also audited all the other ioctls and did not find any other occurences
of this error.

Index: /trunk/libxvmc/viaLowLevelPro.c
===================================================================
--- /trunk/libxvmc/viaLowLevelPro.c (revision 415)
+++ /trunk/libxvmc/viaLowLevelPro.c (revision 694)
@@ -1461,5 +1461,5 @@
     if (size != mem->size) {
 	if (mem->size)
-	    drmCommandWrite(xl->fd, DRM_VIA_FREEMEM, mem, sizeof(mem));
+	    drmCommandWrite(xl->fd, DRM_VIA_FREEMEM, mem, sizeof(*mem));
 	mem->context = *(xl->drmcontext);
 	mem->size = size;
@@ -1467,5 +1467,5 @@
 
 	if (((ret = drmCommandWriteRead(xl->fd, DRM_VIA_ALLOCMEM, mem,
-			sizeof(mem))) < 0) || mem->size != size) {
+			sizeof(*mem))) < 0) || mem->size != size) {
 	    mem->size = 0;
 	    return -1;
@@ -1485,5 +1485,5 @@
 
     if (mem->size)
-	drmCommandWrite(xl->fd, DRM_VIA_FREEMEM, mem, sizeof(mem));
+	drmCommandWrite(xl->fd, DRM_VIA_FREEMEM, mem, sizeof(*mem));
     mem->size = 0;
 }