bltouch: handle antclabs v3 possible EMI with X in G28 & G29

Optional, but may reduce issues on the U30... double check the wiring...

Note: Could make issues during G29 if your "tubing" is a bit "short"
      Be sure there is enough length to reach end of X, if attached..

define BLTOUCH_EMI_X to try, if needed...

Marlin/src/gcode/bedlevel/abl/G29.cpp

@@ -425,6 +425,10 @@ G29_TYPE GcodeSuite::G29() {
 
     // Deploy certain probes before starting probing
     #if HAS_BED_PROBE
+      #ifdef BLTOUCH_EMI_X
+        X_disable(); // optional, but the antclabs can have EMI noise issues,
+                     // if X (or E) motor wires are in same pipe as PWM (on the U30)
+      #endif
       if (ENABLED(BLTOUCH))
         do_z_clearance(Z_CLEARANCE_DEPLOY_PROBE);
       else if (probe.deploy()) {
@@ -712,6 +716,9 @@ G29_TYPE GcodeSuite::G29() {
     TERN_(HAS_STATUS_MESSAGE, ui.reset_status());
 
     // Stow the probe. No raise for FIX_MOUNTED_PROBE.
+    #ifdef BLTOUCH_EMI_X
+      X_disable(); // EMI noise
+    #endif
     if (probe.stow()) {
       set_bed_leveling_enabled(abl.reenable);
       abl.measured_z = NAN;
@@ -896,6 +903,10 @@ G29_TYPE GcodeSuite::G29() {
     DWIN_CompletedLeveling();
   #endif
 
+  #ifdef BLTOUCH_EMI_X
+    X_enable(); // restore disabled X driver
+  #endif
+
   report_current_position();
 
   TERN_(FULL_REPORT_TO_HOST_FEATURE, set_and_report_grblstate(M_IDLE));

Marlin/src/module/motion.cpp

@@ -1758,6 +1758,9 @@ void prepare_line_to_destination() {
     //
     #if HOMING_Z_WITH_PROBE
       if (axis == Z_AXIS) {
+        #ifdef BLTOUCH_EMI_X
+          X_disable(); // workaround for the antclabs EMI noise
+        #endif
         if (TERN0(BLTOUCH, bltouch.deploy())) return;   // BLTouch was deployed above, but get the alarm state.
         if (TERN0(PROBE_TARE, probe.tare())) return;
       }

Marlin/src/module/probe.cpp

@@ -73,7 +73,7 @@
   #include "../feature/tmc_util.h"
 #endif
 
-#if HAS_QUIET_PROBING
+#if HAS_QUIET_PROBING || HOMING_Z_WITH_PROBE
   #include "stepper/indirection.h"
 #endif
 
@@ -775,6 +775,9 @@ float Probe::probe_at_point(const_float_t rx, const_float_t ry, const ProbePtRai
   do_blocking_move_to(npos, feedRate_t(XY_PROBE_FEEDRATE_MM_S));
 
   float measured_z = NAN;
+  #ifdef BLTOUCH_EMI_X
+    X_disable(); // Antclabs EMI noise (not seen on the 3DTouch)
+  #endif
   if (!deploy()) measured_z = run_z_probe(sanity_check) + offset.z;
   if (!isnan(measured_z)) {
     const bool big_raise = raise_after == PROBE_PT_BIG_RAISE;