Remove osmesa

It's redundant with EGL surfaceless and it doesn't have much use.

It's also available from the amber branch, so distros should get it from
there if they want to continue packaging it.

Reviewed-by: Adam Jackson <ajax@redhat.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/33836>

.gitlab-ci/build/gitlab-ci.yml

@@ -241,7 +241,6 @@ debian-build-testing:
     BUILDTYPE: "debugoptimized"
     EXTRA_OPTION: >
       -D spirv-to-dxil=true
-      -D osmesa=true
       -D tools=drm-shim,etnaviv,freedreno,glsl,intel,intel-ui,nir,nouveau,lima,panfrost,asahi
       -D perfetto=true
     S3_ARTIFACT_NAME: debian-build-testing
@@ -273,7 +272,6 @@ debian-release:
     VULKAN_DRIVERS: "swrast,intel_hasvk,imagination-experimental,microsoft-experimental"
     EXTRA_OPTION: >
       -D spirv-to-dxil=true
-      -D osmesa=true
       -D tools=all
       -D mesa-clc=enabled
       -D precomp-compiler=enabled
@@ -344,7 +342,6 @@ fedora-release:
       -D glvnd=enabled
       -D platforms=x11,wayland
     EXTRA_OPTION: >
-      -D osmesa=true
       -D tools=drm-shim,etnaviv,freedreno,glsl,intel,nir,nouveau,lima,panfrost,imagination
       -D vulkan-layers=device-select,overlay
       -D intel-rt=enabled
@@ -450,7 +447,6 @@ debian-android:
       -D gbm=enabled
       -D egl=enabled
       -D platforms=x11,wayland
-      -D osmesa=false
     GALLIUM_ST: >
       -D gallium-vdpau=disabled
       -D gallium-va=disabled
@@ -677,7 +673,6 @@ debian-clang:
     VULKAN_DRIVERS: intel,amd,freedreno,broadcom,virtio,swrast,panfrost,imagination-experimental,microsoft-experimental,nouveau
     EXTRA_OPTION:
       -D spirv-to-dxil=true
-      -D osmesa=true
       -D imagination-srv=true
       -D tools=drm-shim,etnaviv,freedreno,glsl,intel,intel-ui,nir,nouveau,lima,panfrost,asahi,imagination
       -D vulkan-layers=device-select,overlay
@@ -743,7 +738,6 @@ debian-vulkan:
       -D gles2=disabled
       -D glvnd=disabled
       -D platforms=x11,wayland
-      -D osmesa=false
     GALLIUM_ST: >
       -D gallium-vdpau=disabled
       -D gallium-va=disabled