drm/xe: Remove stale declaration of xe_mmio_probe_vram()

The declaration of xe_mmio_probe_vram() became useless since
commit 638d1c79 ("drm/xe: Promote VRAM initialization function to
own file"). Remove it.
Signed-off-by: Gustavo Sousa <gustavo.sousa@intel.com>
Reviewed-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240722190524.71548-2-gustavo.sousa@intel.com

drivers/gpu/drm/xe/xe_mmio.h

@@ -22,7 +22,6 @@ u32 xe_mmio_rmw32(struct xe_gt *gt, struct xe_reg reg, u32 clr, u32 set);
 int xe_mmio_write32_and_verify(struct xe_gt *gt, struct xe_reg reg, u32 val, u32 mask, u32 eval);
 bool xe_mmio_in_range(const struct xe_gt *gt, const struct xe_mmio_range *range, struct xe_reg reg);
 
-int xe_mmio_probe_vram(struct xe_device *xe);
 u64 xe_mmio_read64_2x32(struct xe_gt *gt, struct xe_reg reg);
 int xe_mmio_wait32(struct xe_gt *gt, struct xe_reg reg, u32 mask, u32 val, u32 timeout_us,
 		   u32 *out_val, bool atomic);