MAINTAINERS: Create dedicated entries for 3rd party toolchains

Create dedicated entries for ARC MWDT, arm compiler 6, and one Api
toolchains.

This helps contributors to identify whom to contact in case of issues
related to those toolchains.

The Zephyr SDK, cross-compile, and other GCC based compilers are covered
as part of the general cmake/toolchain,compiler,linker,bintools entry in
the MAINTAINERS file.

(cherry picked from commit 2f79f5e)

Original-Fixes: zephyrproject-rtos#63738
Original-Signed-off-by: Torsten Rasmussen <Torsten.Rasmussen@nordicsemi.no>
GitOrigin-RevId: 2f79f5e
Change-Id: Ic01f3f9411ac143e1faae10e19c13ebe60f818a4
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/zephyr/+/4933966
Tested-by: Keith Short <keithshort@chromium.org>
Tested-by: ChromeOS Prod (Robot) <chromeos-ci-prod@chromeos-bot.iam.gserviceaccount.com>
Reviewed-by: Keith Short <keithshort@chromium.org>
Commit-Queue: Keith Short <keithshort@chromium.org>

MAINTAINERS.yml

@@ -2795,7 +2795,7 @@ TF-M Integration:
   labels:
     - "area: TF-M"
 
-Toolchain Integration:
+"Toolchain Integration":
   status: maintained
   maintainers:
     - tejlmand
@@ -2809,6 +2809,40 @@ Toolchain Integration:
   labels:
     - "area: Toolchains"
 
+"Toolchain ARC MWDT":
+  status: maintained
+  maintainers:
+    - evgeniy-paltsev
+    - abrodkin
+  files:
+    - cmake/*/arcmwdt/
+    - include/zephyr/toolchain/mwdt.h
+    - lib/libc/arcmwdt/*
+  labels:
+    - "area: Toolchains"
+
+"Toolchain arm compiler 6":
+  status: maintained
+  maintainers:
+    - tejlmand
+  files:
+    - cmake/*/armclang/
+    - cmake/linker/armlink/
+    - include/zephyr/toolchain/armclang.h
+    - lib/libc/armstdc/*
+  labels:
+    - "area: Toolchains"
+
+"Toolchain oneApi":
+  status: maintained
+  maintainers:
+    - nashif
+  files:
+    - cmake/*/oneApi/
+    - cmake/compiler/icx/
+  labels:
+    - "area: Toolchains"
+
 Tracing:
   status: maintained
   maintainers: