FwmarkServer - fix a bugprone-branch-clone compiler warning

Fixes:
  system/netd/server/FwmarkServer.cpp:253:9: warning: switch has 3 consecutive identical branches [bugprone-branch-clone]

Test: builds
Bug: 153035880
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Change-Id: I78aa7f7ebe2541095df1bba3354fbb9b8365ae1c
Merged-In: I78aa7f7ebe2541095df1bba3354fbb9b8365ae1c
diff --git a/server/FwmarkServer.cpp b/server/FwmarkServer.cpp
index bc033fa..60981e5 100644
--- a/server/FwmarkServer.cpp
+++ b/server/FwmarkServer.cpp
@@ -250,14 +250,8 @@
             break;
         }
 
-        case FwmarkCommand::ON_SENDMMSG: {
-            return 0;
-        }
-
-        case FwmarkCommand::ON_SENDMSG: {
-            return 0;
-        }
-
+        case FwmarkCommand::ON_SENDMMSG:
+        case FwmarkCommand::ON_SENDMSG:
         case FwmarkCommand::ON_SENDTO: {
             return 0;
         }