Disable joysticks per default for now

It seems that various different devices register as
Joysticks on linux, and their presence has caused
lots of confusion amongst minetest users.

Therefore, disable the joystick feature.

Closes #4261
Closes #4221

builtin/settingtypes.txt

@@ -105,7 +105,7 @@ random_input (Random input) bool false
 continuous_forward (Continuous forward) bool false
 
 #    Enable Joysticks
-enable_joysticks (Enable Joysticks) bool true
+enable_joysticks (Enable Joysticks) bool false
 
 #    The time in seconds it takes between repeated events
 #    when holding down a joystick button combination.

src/defaultsettings.cpp

@@ -116,7 +116,7 @@ void set_default_settings(Settings *settings)
 	settings->setDefault("free_move", "false");
 	settings->setDefault("noclip", "false");
 	settings->setDefault("continuous_forward", "false");
-	settings->setDefault("enable_joysticks", "true");
+	settings->setDefault("enable_joysticks", "false");
 	settings->setDefault("repeat_joystick_button_time", "0.17");
 	settings->setDefault("joystick_frustum_sensitivity", "170");
 	settings->setDefault("cinematic", "false");