Remove a redundant check in statsd socket code.

The original liblog code has this additional check because there may be multiple writers registered,
there is a for-loop and the retVal is set to be the FIRST error. Statsd doesn't need it because it
 only has one writer.

Test: locally tested.
Change-Id: I03f0015d0c29eba19eb2b5ea145380cb98fb2509