MAINTAINERS: Mark subsys/mgmt/osdp as maintained

subsys/mgmt/osdp _has_ a dedicated maintainer who will rush to address
any issues identified :)

Also, add @adakus and @r2r0 as collaborators since they are using this
subsystem in production and have agreed to review, test, and report issues
for this subsystem in future.

Signed-off-by: Siddharth Chandrasekaran <[email protected]>

Author: sidcha

MAINTAINERS.yml

@@ -1443,9 +1443,12 @@ Modbus:
     - "area: modbus"
 
 OSDP:
-  status: odd fixes
-  collaborators:
+  status: maintained
+  maintainers:
     - sidcha
+  collaborators:
+    - adakus
+    - r2r0
   files:
     - subsys/mgmt/osdp/
     - include/zephyr/mgmt/osdp.h