Tweak some lambdas

Marlin/src/feature/bedlevel/ubl/ubl_G29.cpp

@@ -1611,7 +1611,7 @@
          * numbers for those locations should be 0.
          */
         #ifdef VALIDATE_MESH_TILT
-          auto d_from = []() { DEBUG_ECHOPGM("D from "); };
+          auto d_from = []{ DEBUG_ECHOPGM("D from "); };
           auto normed = [&](const xy_pos_t &pos, const float &zadd) {
             return normal.x * pos.x + normal.y * pos.y + zadd;
           };