[Intel-gfx] [PATCH]i830_display.c:don't disable vga centering bit.

[Ma Ling]

commit id b9f5915ce812144ffd9d2aa42e8ba856129c35e,
which resolved bug #17235, but generate new regression-bug #19715. 
This patch intends to resolve bug #17235, and avoid regression as well.
We have successfully re-tested it for bug #17235 and #19715 respectively.

---
 src/i830_display.c |    5 -----
 1 files changed, 0 insertions(+), 5 deletions(-)

diff --git a/src/i830_display.c b/src/i830_display.c
index 7a8e96d..d4b7943 100644
--- a/src/i830_display.c
+++ b/src/i830_display.c
@@ -808,13 +808,8 @@ i830_disable_vga_plane (xf86CrtcPtr crtc)
 
     vgacntrl |= VGA_DISP_DISABLE;
 
-    /* disable center mode */
-    if (IS_I9XX(pI830))
-	vgacntrl &= ~(3 << 24);
-
     OUTREG(VGACNTRL, vgacntrl);
     i830WaitForVblank(pScrn);
-
 }
 
 /**
-- 
1.5.4.4