Cast DELTA_PRINTABLE_RADIUS to float in sq()

Addressing #5625

Marlin/Marlin_main.cpp

@@ -2937,7 +2937,7 @@ bool position_is_reachable(float target[XYZ]
       return HYPOT2(dx - SCARA_OFFSET_X, dy - SCARA_OFFSET_Y) <= sq(L1 + L2);
     #endif
   #elif ENABLED(DELTA)
-    return HYPOT2(dx, dy) <= sq(DELTA_PRINTABLE_RADIUS);
+    return HYPOT2(dx, dy) <= sq((float)(DELTA_PRINTABLE_RADIUS));
   #else
     const float dz = RAW_Z_POSITION(target[Z_AXIS]);
     return dx >= X_MIN_POS - 0.0001 && dx <= X_MAX_POS + 0.0001

Marlin/ultralcd.cpp

@@ -1554,7 +1554,7 @@ KeepDrawing:
       // This assumes the center is 0,0
       #if ENABLED(DELTA)
         if (axis != Z_AXIS) {
-          max = sqrt(sq(DELTA_PRINTABLE_RADIUS) - sq(current_position[Y_AXIS - axis]));
+          max = sqrt(sq((float)(DELTA_PRINTABLE_RADIUS)) - sq(current_position[Y_AXIS - axis]));
           min = -max;
         }
       #endif