fim: fix cross / strictDeps build

[FliegendeWurst]

ref. #178468

Things done

• Built on platform(s)
  • x86_64-linux: and cross to aarch64
  • aarch64-linux
  • x86_64-darwin
  • aarch64-darwin
• Fits CONTRIBUTING.md.

[uninsane]

haven't tried building it, but aside from the patch substitution the rest LGTM

feedback addressed

[uninsane]

new version breaks native compilation. error message suggests to use substitute (or substituteAll)

$ nix-build -A fim
these 2 derivations will be built:
  /nix/store/abf4yr0jwmginynh2mk7vip8q5czq9y0-native-tools.patch.drv
  /nix/store/w2q0r4s43xlzcc0a6bsl1s9xs5sc3wks-fim-0.7.drv
building '/nix/store/abf4yr0jwmginynh2mk7vip8q5czq9y0-native-tools.patch.drv'...
Running phase: patchPhase
Running phase: updateAutotoolsGnuConfigScriptsPhase
Running phase: configurePhase
no configure script, doing nothing
Running phase: buildPhase
Running phase: checkPhase
The following look like unsubstituted Nix identifiers that remain in /nix/store/118rabdw0xy671p8ijsdxnxvn1g7nbxb-native-tools.patch:
@FIM_WANT_CUSTOM_HARDCODED_CONSOLEFONT_TRUE@
@HAVE_RUNNABLE_TESTS_TRUE@
@FIM_WANT_CUSTOM_HARDCODED_CONSOLEFONT_TRUE@
@HAVE_RUNNABLE_TESTS_TRUE@
Use the more precise `substitute` function if this check is in error.

[FliegendeWurst]

Fixed. Bit of a silly check since uppercase variables can't be substituted anyway #28086

[uninsane]

$ nix-build -A pkgsCross.aarch64-multiplatform.fim
...
checking for libpng-config... no

native build has png support: would ideally also have png support when cross compiling (or at the very least, change up the pngSupport package option to reflect reality).

[FliegendeWurst]

Since we switched SDL to SDL_compat -> sdl2-compat -> sdl3 -> ... -> Qt, x11Support now defaults to false for cross.

libpng fixed.

[uninsane]

$ nix-build -A pkgsCross.aarch64-multiplatform.fim
$ head -n1 ./result/bin/fimgs
#!/bin/bash

needs its shebang fixed

[uninsane]

also, cross is building without ascii art support:

configure: Enabling aalib driver.
checking for aalib-config... no
configure: WARNING: ***  no aalib-config ? ***

can likely be fixed the same way png was fixed.

other than that i think it's correct.

[FliegendeWurst]

Fixed, and I've now just compared the build logs, as I should have perhaps done from the start. And found two more things that differed, fixed via configureFlags.