Address the warning given by haxe 5.0.

[qlambert-pro]

I have been experimenting with the upstream version of haxe and ran into warnings this PR applies the suggestion given in the messages.

[WARNING] /usr/share/haxe/lib/deepnightlibs/git/src/dn/Tweenie.hx:381: characters 6-13

 381 |  #if display
     |      ^^^^^^^
     | (WIfDisplay) Using `display` here doesn't work because #if conditions are evaluated at parse time. In macros, use `haxe.macro.Context.defined("display")` instead.

[WARNING] /usr/share/haxe/lib/deepnightlibs/git/src/dn/Tweenie.hx:396: characters 6-13

 396 |  #if display
     |      ^^^^^^^
     | (WIfDisplay) Using `display` here doesn't work because #if conditions are evaluated at parse time. In macros, use `haxe.macro.Context.defined("display")` instead.
     
[WARNING] /usr/share/haxe/lib/deepnightlibs/git/src/dn/Cooldown.hx:94: characters 6-13

  94 |  #if display
     |      ^^^^^^^
     | (WIfDisplay) Using `display` here doesn't work because #if conditions are evaluated at parse time. In macros, use `haxe.macro.Context.defined("display")` instead.

[kLabz]

That's not how you should do it Oo (and it should actually give compilation errors)

Basically here the #if lines should be dropped.
haxe.macro.Context.defined("display") is for macro code, not #if conditions.

[qlambert-pro]

Is that what you meant?

i.e. only keep the macro definitions of the functions? I guess more importantly the ones with the actual implementation.