Various fixes for compiler warnings

add BLTouch-related messages in english and (rusty) french;
add missing endstops.h in ultralcd.cpp;
fix misc. compiler warnings;
fix lsf_reset - ZERO macro can't handle a pointer as it would only memset the size of the pointer, not the size of the entire struct

Marlin/language_en.h

@@ -417,6 +417,12 @@
 #ifndef MSG_BLTOUCH_RESET
   #define MSG_BLTOUCH_RESET                   _UxGT("Reset BLTouch")
 #endif
+#ifndef MSG_BLTOUCH_DEPLOY
+  #define MSG_BLTOUCH_DEPLOY                  _UxGT("Deploy BLTouch")
+#endif
+#ifndef MSG_BLTOUCH_STOW
+  #define MSG_BLTOUCH_STOW                    _UxGT("Stow BLTouch")
+#endif
 #ifndef MSG_HOME
   #define MSG_HOME                            _UxGT("Home") // Used as MSG_HOME " " MSG_X MSG_Y MSG_Z " " MSG_FIRST
 #endif