Don't use check for tests

The tests are so simple that we could rather just add implement
that tiny little function ourself instead of depending on another
library and not be able to test it on all platforms..

Change-Id: I983b511fc2517b21bfdf136900b32f1e33d4de40
Reviewed-on: http://review.couchbase.org/25984
Tested-by: Trond Norbye <trond.norbye@gmail.com>
Reviewed-by: Trond Norbye <trond.norbye@gmail.com>