Removes references to mibstore.h and miInitializeBackingStore, which
have been removed from xorg-server.  Zack Rusin <zackr@vmware.com>
wrote: "It was a noop for at least 5 years and it has been removed."
See: http://patches.openembedded.org/patch/46133/

--- xf86-video-tga-1.2.2/src/tga_accel.c.~1~	2012-07-15 23:54:04.000000000 -0400
+++ xf86-video-tga-1.2.2/src/tga_accel.c	2014-12-19 01:40:27.535913013 -0500
@@ -37,7 +37,6 @@
 #include "xf86cmap.h"
 #include "mipointer.h"
 
-#include "mibstore.h"
 #include "miline.h"
 
 #include "tga_regs.h"
--- xf86-video-tga-1.2.2/src/tga_driver.c.~1~	2012-07-15 23:54:28.000000000 -0400
+++ xf86-video-tga-1.2.2/src/tga_driver.c	2014-12-19 01:40:48.756018238 -0500
@@ -46,8 +46,6 @@
 
 /* software cursor */
 #include "mipointer.h"
-/* backing store */
-#include "mibstore.h"
 
 /*  #include "mibank.h" */
 /* colormap manipulation */
@@ -1451,7 +1449,6 @@
     
     fbPictureInit (pScreen, 0, 0);
     
-    miInitializeBackingStore(pScreen);
     xf86SetBackingStore(pScreen);
     xf86SetSilkenMouse(pScreen);