🔧 Safer default for Z_MIN_PROBE_PIN override (#25524)

Co-authored-by: Scott Lahteine <thinkyhead@users.noreply.github.com>

Marlin/Configuration.h

@@ -1345,19 +1345,17 @@
 /**
  * Z_MIN_PROBE_PIN
  *
- * Define this pin if the probe is not connected to Z_MIN_PIN.
- * If not defined the default pin for the selected MOTHERBOARD
- * will be used. Most of the time the default is what you want.
+ * Override this pin only if the probe cannot be connected to
+ * the default Z_MIN_PROBE_PIN for the selected MOTHERBOARD.
  *
  *  - The simplest option is to use a free endstop connector.
  *  - Use 5V for powered (usually inductive) sensors.
  *
- *  - RAMPS 1.3/1.4 boards may use the 5V, GND, and Aux4->D32 pin:
- *    - For simple switches connect...
- *      - normally-closed switches to GND and D32.
- *      - normally-open switches to 5V and D32.
+ *  - For simple switches...
+ *    - Normally-closed (NC) also connect to GND.
+ *    - Normally-open (NO) also connect to 5V.
  */
-//#define Z_MIN_PROBE_PIN 32 // Pin 32 is the RAMPS default
+//#define Z_MIN_PROBE_PIN -1
 
 /**
  * Probe Type