drm/vmwgfx/vmwgfx_context: Demote kernel-doc abuses

Fixes the following W=1 kernel build warning(s):

 drivers/gpu/drm/vmwgfx/vmwgfx_context.c:121: warning: Function parameter or member 'dev_priv' not described in 'vmw_context_cotables_unref'
 drivers/gpu/drm/vmwgfx/vmwgfx_context.c:121: warning: Function parameter or member 'uctx' not described in 'vmw_context_cotables_unref'
 drivers/gpu/drm/vmwgfx/vmwgfx_context.c:681: warning: Function parameter or member 'base' not described in 'vmw_user_context_base_to_res'
 drivers/gpu/drm/vmwgfx/vmwgfx_context.c:707: warning: Function parameter or member 'p_base' not described in 'vmw_user_context_base_release'

Cc: VMware Graphics <linux-graphics-maintainer@vmware.com>
Cc: Roland Scheidegger <sroland@vmware.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Zack Rusin <zackr@vmware.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210115181313.3431493-29-lee.jones@linaro.org

drivers/gpu/drm/vmwgfx/vmwgfx_context.c

@@ -112,7 +112,7 @@ static const struct vmw_res_func vmw_dx_context_func = {
 	.unbind = vmw_dx_context_unbind
 };
 
-/**
+/*
  * Context management:
  */
 
@@ -672,7 +672,7 @@ static int vmw_dx_context_destroy(struct vmw_resource *res)
 	return 0;
 }
 
-/**
+/*
  * User-space context management:
  */
 
@@ -698,7 +698,7 @@ static void vmw_user_context_free(struct vmw_resource *res)
 			    vmw_user_context_size);
 }
 
-/**
+/*
  * This function is called when user space has no more references on the
  * base object. It releases the base-object's reference on the resource object.
  */