Correct invalid assert use

source/blender/editors/gpencil/gpencil_brush.c

@@ -710,7 +710,7 @@ static bool gp_brush_randomize_apply(tGP_BrushEditData *gso, bGPDstroke *gps, in
 			}
 			else {
 				/* ERROR */
-				BLI_assert("3D stroke being sculpted in non-3D view");
+				BLI_assert(!"3D stroke being sculpted in non-3D view");
 			}
 		}
 		else {

source/blender/editors/render/render_shading.c

@@ -1818,7 +1818,7 @@ static void paste_mtex_copybuf(ID *id)
 			mtex = &(((FreestyleLineStyle *)id)->mtex[(int)((FreestyleLineStyle *)id)->texact]);
 			break;
 		default:
-			BLI_assert("invalid id type");
+			BLI_assert(!"invalid id type");
 			return;
 	}