wasi: remove unecessary null check

As reported by coverity the null check is done after earlier code has already derefenced options.envp. Either we should null check earlier uses or this check is not necessary. Since options.envp is created with new which should throw an exception intead of returning null, it should be safe to assume the null check is not required.

Signed-off-by: Michael Dawson mdawson@devrus.com