randr12: Initialize and keep track of updates to VidMode extension gamma value.

This way clients querying the gamma value via the VidMode extension at least
get the last value set via the same, rather than always something bogus.

Signed-off-by: Michel Dänzer <daenzer@vmware.com>

hw/xfree86/common/xf86Helper.c

@@ -919,11 +919,6 @@ Bool
 xf86SetGamma(ScrnInfoPtr scrp, Gamma gamma)
 {
     MessageType from = X_DEFAULT;
-    /* Pretend we succeeded if we support better a gamma system.
-     * This avoids a confusing message.
-     */
-    if (xf86_crtc_supports_gamma(scrp))
-	return TRUE;
 #if 0
     xf86MonPtr DDC = (xf86MonPtr)(scrp->monitor->DDC);
 #endif
@@ -955,6 +950,11 @@ xf86SetGamma(ScrnInfoPtr scrp, Gamma gamma)
 	scrp->gamma.green = 1.0;
 	scrp->gamma.blue = 1.0;
     }
+    /* Pretend we succeeded if we support better a gamma system.
+     * This avoids a confusing message.
+     */
+    if (xf86_crtc_supports_gamma(scrp))
+	return TRUE;
     xf86DrvMsg(scrp->scrnIndex, from,
 	       "Using gamma correction (%.1f, %.1f, %.1f)\n",
 	       scrp->gamma.red, scrp->gamma.green, scrp->gamma.blue);

hw/xfree86/modes/xf86RandR12.c

@@ -1740,6 +1740,8 @@ xf86RandR12ChangeGamma(int scrnIndex, Gamma gamma)
 
     xfree(points);
 
+    pScrn->gamma = gamma;
+
     return Success;
 }