🎨 Fix/adjust warnings (#24225)

Marlin/src/module/stepper.cpp

@@ -611,7 +611,7 @@ void Stepper::set_directions() {
   #if DISABLED(LIN_ADVANCE)
     #if ENABLED(MIXING_EXTRUDER)
        // Because this is valid for the whole block we don't know
-       // what e-steppers will step. Likely all. Set all.
+       // what E steppers will step. Likely all. Set all.
       if (motor_direction(E_AXIS)) {
         MIXER_STEPPER_LOOP(j) REV_E_DIR(j);
         count_direction.e = -1;

Marlin/src/module/stepper.h

@@ -214,7 +214,7 @@
     // Directions are set up for MIXING_STEPPERS - like before.
     // Finding the right stepper may last up to MIXING_STEPPERS loops in get_next_stepper().
     //   These loops are a bit faster than advancing a bresenham counter.
-    // Always only one e-stepper is stepped.
+    // Always only one E stepper is stepped.
     #define MIN_ISR_LA_LOOP_CYCLES ((MIXING_STEPPERS) * (ISR_STEPPER_CYCLES))
   #else
     #define MIN_ISR_LA_LOOP_CYCLES ISR_STEPPER_CYCLES