ipvs: remove unused variable

This patch uses the following coccinelle script to remove
a variable that was simply used to store the return
value of a function call before returning it:

@@
identifier len,f;
@@

-int len;
 ... when != len
     when strict
-len =
+return
        f(...);
-return len;

Signed-off-by: Arushi Singhal <arushisinghal19971997@gmail.com>
Signed-off-by: Simon Horman <horms@verge.net.au>