Unify bits, android_arch, macos_arch ios_arch into arch, support non-x86

Unify arguments and add support for ARM64 and RV64 Linux

test/demo/main.tscn

@@ -12,16 +12,10 @@ offset_left = 194.0
 offset_top = -2.0
 offset_right = 234.0
 offset_bottom = 21.0
-__meta__ = {
-"_edit_use_anchors_": false
-}
 
 [node name="Button" type="Button" parent="."]
 offset_right = 79.0
 offset_bottom = 29.0
 text = "Click me!"
-__meta__ = {
-"_edit_use_anchors_": false
-}
 
 [connection signal="custom_signal" from="Example" to="." method="_on_Example_custom_signal"]