render: drop libEGL dependency if gles2 is disabled

[jbeich]

Disabling gles2 currently violates reproducibility due to opportunistic lookup of libEGL even when auto-detection is disabled.

$ meson setup --auto-features=disabled _build
$ readelf -d _build/libwlroots.so | grep NEEDED.\*GL
 0x0000000000000001 NEEDED               Shared library: [libEGL.so.1]
$ nm --undefined-only -D _build/libwlroots.so | fgrep egl
                 U eglBindAPI
                 U eglCreateContext
                 U eglDestroyContext
                 U eglGetCurrentContext
                 U eglGetCurrentDisplay
                 U eglGetCurrentSurface
                 U eglGetError
                 U eglGetProcAddress
                 U eglInitialize
                 U eglMakeCurrent
                 U eglQueryContext
                 U eglQueryString
                 U eglReleaseThread
                 U eglTerminate

[emersion]

Hm, this isn't quite right. If running with auto, we'll want to look for the egl dep, and disable the gles2 renderer if it's missing. Here the egl dep is mandatory.

[emersion]

FWIW, I think we just need to wrap the original code as-is in the if 'gles2' in renderers or 'auto' in renderers condition you've added above and it should be good to go.

[emersion]

wlroots has migrated to gitlab.freedesktop.org. This pull request has been moved to:

https://gitlab.freedesktop.org/wlroots/wlroots/-/merge_requests/3241