Convert bsd.sdl.mk into Uses/sdl.mk

[AMDmi3]

Summary

• Convert bsd.sdl.mk into Uses feature
• Simplify code a bit

Test Plan

Exp-run is needed

[mat]

Mk/Uses/sdl.mk

78

It would probably be a better idea to change this to a DEV_ERROR, and to move it in Mk/bsd.sanity.mk, and to patch the dozen ports or so that use USE_SDL=yes or opt_USE= sdl=yes.

Mk/bsd.port.mk

1426–1429

I was going to suggest fixing those ports too, but there are quite a few.

[AMDmi3]

Mk/Uses/sdl.mk

78

Agreed, already working on this.

[AMDmi3]

Mk/bsd.port.mk

1426–1429

Yep, I'd prefer to convert ports gradually like it's done for USE_GNOME and USE_GL. Number of USE_SDL ports is comparable to USE_GL ports.

[mat]

Mk/bsd.port.mk

1426–1429

Well, thing is, having it done gradually is not the nice thing to do, because you end up doing half the job and asking the other ports to finish it :-)

Technically, the way it was done for USE_GNOME or USE_GL was ok, but it was humanly wrong.

[AMDmi3]

Remove support for USE_SDL=yes (all ports using USE_SDL=yes were fixed)

[mat]

Could you replace all the tests doing:

.if ${foo:Mbar} != ""

with a much simpler:

.if ${foo:Mbar}

and the:

.if ${foo:Mbar} == ""

with:

.if empty(foo:Mbar)

The time when our make required these constructions is long gone.

[AMDmi3]

Modernize make constructs

[mat]

This look ok to me. Feel free to ask for an exp-run.

[AMDmi3]

@mat sorry, I though you've marked this as accepted. Exp-run was OK anyway: https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=235561