drm/vmwgfx: Add SVGA_3D_CMD_DEFINE_GB_SURFACE_V4 to command array.

Without this definition device errors will display the command name
as (null) when debug logging is enabled.

Signed-off-by: Ian Forbes <ian.forbes@broadcom.com>
Signed-off-by: Zack Rusin <zack.rusin@broadcom.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240108211655.13187-1-ian.forbes@broadcom.com