qemacs: fix cross-compilation

[ghost]

Description of changes

This fixes cross-compilation for qemacs. It also adds enableX11 parameter.

Things done

• Built on platform(s)
  • x86_64-linux
  • powerpc64le-linux
  • aarch64-linux
  • mips64el-linux (cross from powerpc64le-linux)
• Tested basic functionality of all binary files (usually in ./result/bin/)
• Fits CONTRIBUTING.md.

[Mindavi]

Build on darwin seems broken, is it related?

[iblech]

Very nice, thank you for your work! I didn't test cross compilation, all the changes look very solid.

I cannot comment on the darwin situation.

[ghost]

Build on darwin seems broken, is it related?

I'm afraid I do not have access to any darwin machines.

[Artturin]

Build on darwin seems broken, is it related?

I'm afraid I do not have access to any darwin machines.

you can request access to https://github.com/winterqt/darwin-build-box if you want

[Artturin]

upstream assumes gcc

[Artturin]

Build on darwin seems broken, is it related?

it's a pre-existing issue, fixed the gcc error but there's still

qe.c:32:31: error: argument to 'section' attribute is not valid for this target: mach-o section specifier requires a segment and section separated by a comma
int (*__initcall_first)(void) __init_call = NULL;
                              ^
./qe.h:581:57: note: expanded from macro '__init_call'
#define __init_call     __attribute__ ((unused,__section__ (".initcall.init")))
                                                            ^
qe.c:33:32: error: argument to 'section' attribute is not valid for this target: mach-o section specifier requires a segment and section separated by a comma
void (*__exitcall_first)(void) __exit_call = NULL;
                               ^
./qe.h:582:57: note: expanded from macro '__exit_call'
#define __exit_call     __attribute__ ((unused,__section__ (".exitcall.exit")))

[Mindavi]

Closed by #209418