Platform: Add support for BL5340 DVK

This adds supports for the Laird Connectivity BL5340 DVK (development kit)
application core, which is based on the nRF5340 SoC.

Signed-off-by: Jamie McCrae <jamie.mccrae@lairdconnect.com>
Change-Id: I062412918d4cbe692748c1a31fef444190f50661
diff --git a/docs/contributing/maintainers.rst b/docs/contributing/maintainers.rst
index ced48d1..8319d00 100644
--- a/docs/contributing/maintainers.rst
+++ b/docs/contributing/maintainers.rst
@@ -122,6 +122,12 @@
     :email: `Raymond.Ngunn@cypress.com <raymond.ngunn@cypress.com>`__
     :github: `RaymondNgun <https://github.com/RaymondNgun>`__
 
+Laird Connectivity Platforms:
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Jamie McCrae
+    :email: `Jamie.McCrae@lairdconnect.com <jamie.mccrae@lairdconnect.com>`__
+    :github: `thedjnk <https://github.com/thedjnk>`__
 
 Nordic Semiconductor Platforms
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~