Enable sched_ext on x86_64 and aarch64

Also remove temporary scx patches, as they are not necessary now.

Link: https://lore.kernel.org/bpf/0a039ded-b67d-4a0c-a851-e3aafff57321@linux.dev/
Signed-off-by: Ihor Solodrai <isolodrai@meta.com>

Author: theihor

.github/scripts/matrix.py

@@ -187,8 +187,8 @@ def tests(self) -> Dict[str, Any]:
         if self.llvm_version >= 18:
             tests_list.append("test_progs_cpuv4")
 
-        # if self.arch in [Arch.X86_64, Arch.AARCH64]:
-        #     tests_list.append("sched_ext")
+        if self.arch in [Arch.X86_64, Arch.AARCH64]:
+            tests_list.append("sched_ext")
 
         # Don't run GCC BPF runner, because too many tests are failing
         # See: https://lore.kernel.org/bpf/87bjw6qpje.fsf@oracle.com/

.github/workflows/kernel-build.yml

@@ -60,7 +60,7 @@ jobs:
         BPF_NEXT_BASE_BRANCH: 'master'
         BPF_NEXT_FETCH_DEPTH: 64 # A bit of history is needed to facilitate incremental builds
         CROSS_COMPILE: ${{ inputs.arch != 'x86_64' && 'true' || '' }}
-        # BUILD_SCHED_EXT_SELFTESTS: ${{ inputs.arch == 'x86_64' || inputs.arch == 'aarch64' && 'true' || '' }}
+        BUILD_SCHED_EXT_SELFTESTS: ${{ inputs.arch == 'x86_64' || inputs.arch == 'aarch64' && 'true' || '' }}
         KBUILD_OUTPUT: ${{ github.workspace }}/kbuild-output
         KERNEL: ${{ inputs.kernel }}
         KERNEL_ROOT: ${{ github.workspace }}