Add support for Ubuntu21.10

Author: surbhat1595

packaging/deb-in/CMakeLists.txt

@@ -100,6 +100,8 @@ ELSEIF(DEB_CODENAME STREQUAL "focal")
   SET (DEB_PLATFORMRELEASE "ubuntu20.04")
 ELSEIF(DEB_CODENAME STREQUAL "hirsute")
   SET (DEB_PLATFORMRELEASE "ubuntu21.04")
+ELSEIF(DEB_CODENAME STREQUAL "impish")
+  SET (DEB_PLATFORMRELEASE "ubuntu21.10")
 ELSE()
   MESSAGE(STATUS
     "Skipping deb packaging on unsupported platform ${DEB_CODENAME}.")