doc: release: 3.7: Add socs folder note

Adds release notes about the addition of a socs folder for
applications to store Kconfig fragments and devicetree overlays

Signed-off-by: Jamie McCrae <[email protected]>

Author: nordicjm

doc/releases/release-notes-3.7.rst

@@ -95,7 +95,11 @@ Boards & SoC Support
 Build system and Infrastructure
 *******************************
 
-* CI-enabled blackbox tests were added in order to verify correctness of the vast majority of Twister flags.
+  * CI-enabled blackbox tests were added in order to verify correctness of the vast majority of Twister flags.
+
+  * A ``socs`` folder for applications has been introduced that allows for Kconfig fragments and
+    devicetree overlays that should apply to any board target using a particular SoC and board
+    qualifier.
 
 * Compiler