[CODEOWNERS][NFC] Update CODEOWNERS (#1329)

Signed-off-by: Tsang, Whitney <[email protected]>

Author: whitneywhtsang

.github/CODEOWNERS

@@ -1,37 +1,2 @@
-* @bader
-
-# Use runtime team as the umbrella for most of the tests
-/SYCL/ @intel/llvm-reviewers-runtime
-
-# SYCL sub-directory matchers are grouped by code owner first, followed by
-# alphabetical order within the group. Please, keep this ordering.
-
-# Group algorithms
-/SYCL/GroupAlgorithm/ @Pennycook @intel/llvm-reviewers-runtime
-/SYCL/GroupLocalMemory/ @Pennycook @intel/llvm-reviewers-runtime
-/SYCL/SubGroup/ @Pennycook @intel/llvm-reviewers-runtime
-/SYCL/SubGroupMask/ @Pennycook @intel/llvm-reviewers-runtime
-
-# Plugin interface for Level Zero
-/SYCL/Plugin/*level-zero* @intel/dpcpp-l0-pi-reviewers
-/SYCL/Plugin/*level_zero* @intel/dpcpp-l0-pi-reviewers
-
-# Explicit SIMD
-/SYCL/ESIMD/ @intel/dpcpp-esimd-reviewers
-
-# BFloat16 conversion
-/SYCL/BFloat16/ @intel/dpcpp-tools-reviewers
-
-# Compiler tests
-/SYCL/AOT/ @intel/dpcpp-tools-reviewers
-/SYCL/DeviceCodeSplit/ @intel/dpcpp-tools-reviewers
-/SYCL/SeparateCompile/ @intel/dpcpp-tools-reviewers
-
-# Printf
-/SYCL/Printf/ @intel/dpcpp-tools-reviewers
-
-# Specialization constant
-/SYCL/SpecConstants/ @intel/dpcpp-tools-reviewers
-
-# invoke_simd
-/SYCL/InvokeSimd/ @intel/dpcpp-esimd-reviewers
+# SYCL MLIR
+* @etiotto @whitneywhtsang