MSVC don't support alarm()

It is just used as a safety net anyway

Change-Id: Ic2861abefe4363a25bdb75a35c826343922df2ba
Reviewed-on: http://review.couchbase.org/31412
Reviewed-by: Trond Norbye <trond.norbye@gmail.com>
Tested-by: Trond Norbye <trond.norbye@gmail.com>