VA/GLX: drop useless casts.
VA/GLX: drop useless casts.

pma1/libva,android-ia/hardware_intel_libva,chenxianqin/vaapi-libva,gbeauchesne/libva,android-ia/hardware_intel_libva,zzhhui/libva,chenxianqin/vaapi-libva,gbeauchesne/libva,Distrotech/libva,01org/iotg-lin-gfx-libva,halleyzhao/libva-fdo,01org/libva-cros,halleyzhao/libva-fdo,pma1/libva,CyanogenMod/android_hardware_intel_libva,Distrotech/libva,zzhhui/libva,01org/libva-cros,01org/libva-cros,halleyzhao/libva-fdo,android-ia/hardware_intel_libva,pma1/libva,CyanogenMod/android_hardware_intel_libva,01org/iotg-lin-gfx-libva,zzhhui/libva,CyanogenMod/android_hardware_intel_libva,chenxianqin/vaapi-libva,Distrotech/libva,gbeauchesne/libva,01org/iotg-lin-gfx-libva