staging: xgifb: Drop some more useless defines

SetLCDStdMode is not supported as of 34c13ee2 ("staging: xgifb: drop
code for legacy VGA modes").

DisableLCD24bpp defined to zero was never realy useful and went away with
aa56b279 ("staging: xgifb: vb_table: delete XGI21_LCDCapList").
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/xgifb/vb_def.h

@@ -44,12 +44,10 @@
 #define SetLCDtoNonExpanding 0x0010
 #define SetLCDDualLink       0x0100
 #define SetLCDLowResolution  0x0200
-#define SetLCDStdMode        0x0400
 
 /* LCD Capability shampoo */
 #define DefaultLCDCap        0x80ea
 #define EnableLCD24bpp       0x0004 /* default */
-#define DisableLCD24bpp      0x0000
 #define LCDPolarity          0x00c0 /* default: SyncNN */
 #define XGI_LCDDualLink      0x0100
 #define EnableSpectrum       0x0200