linux-user/syscall.c: Don't skip stracing for fcntl64 failure case

In an fcntl64 failure path, we were returning directly rather than
simply breaking out of the switch statement. This skips the strace
code for printing the syscall return value, so don't do that.

Acked-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index c84cc65..2bf9e7e 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -7521,8 +7521,10 @@
 #endif
 
 	cmd = target_to_host_fcntl_cmd(arg2);
-	if (cmd == -TARGET_EINVAL)
-		return cmd;
+        if (cmd == -TARGET_EINVAL) {
+            ret = cmd;
+            break;
+        }
 
         switch(arg2) {
         case TARGET_F_GETLK64: