batt_smbus: Commentted out button press detection

The button press detection relies on reading the MANUFACTURER_DATA
register. The implementation of what information is returned when reading
this register differs from manufacturer to manufacturer.

This has been commented out until an elegant solution can be found to detect
the battery shutdown on different batteries manufactured by different
manufacturers.

src/drivers/batt_smbus/batt_smbus.cpp

@@ -451,6 +451,7 @@ BATT_SMBUS::cycle()
 			}
 		}
 
+        /*
 		// read the button press indicator
         if (read_block(BATT_SMBUS_MANUFACTURER_DATA, buff, 6, false) == 6) {
 			bool pressed = (buff[1] >> 3) & 0x01;
@@ -471,6 +472,7 @@ BATT_SMBUS::cycle()
 				new_report.is_powering_off = false;
 			}
 		}
+        */
 
 		// publish to orb
 		if (_batt_topic != -1) {