xfree86: Remove memClk from ScrnInfoRec

Never set by the core, not used in any modern driver.

Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Aaron Plattner <aplattner@nvidia.com>
Acked-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Adam Jackson <ajax@redhat.com>

hw/xfree86/common/xf86str.h

@@ -649,7 +649,6 @@ typedef struct _ScrnInfoRec {
     int videoRam;               /* amount of video ram (kb) */
     unsigned long memPhysBase;  /* Physical address of FB */
     unsigned long fbOffset;     /* Offset of FB in the above */
-    int memClk;                 /* memory clock */
     Bool flipPixels;            /* swap default black/white */
     void *options;
 

hw/xfree86/doc/ddxDesign.xml

@@ -1209,7 +1209,6 @@ Here is what <function>InitOutput()</function> does:
           clock[]               (if not programmable)
           videoRam
           memBase
-          memClk
           driverPrivate
           chipID
           chipRev