doc: release notes: ARC

2.7 release notes for ARC related changes

Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Evgeniy Paltsev <PaltsevEvgeniy@gmail.com>
diff --git a/doc/releases/release-notes-2.7.rst b/doc/releases/release-notes-2.7.rst
index 31cb276..58844ad 100644
--- a/doc/releases/release-notes-2.7.rst
+++ b/doc/releases/release-notes-2.7.rst
@@ -141,6 +141,13 @@
 
 * ARC
 
+  * Add SMP support to ARCv3 HS6x
+  * Add MWDT C library support
+  * Add basic C++ support with MWDT toolchain
+  * Add MPUv3 and MPUv6 support
+  * Remove dead PM code from ARC core interrupt controller driver
+  * Add updating arc connect debug mask dynamically
+
 
 * ARM
 
@@ -246,6 +253,10 @@
 
 * Changes for ARC boards:
 
+  * Implement 'run' command for SMP nSIM simulation board
+  * Enable upstream verification on QEMU ARCv3 HS6x board (qemu_arc_hs6x)
+  * Implement creg GPIO driver and add it to hsdk and em_starterkit boards
+
 
 * Changes for ARM boards: