Rename syncreq.[ch] to otpctrl.[ch]
This gives us a place to handle all OTP related controls. Also,
genericize otpctrl_present() so that the OID can be specified as an
argument to the function call.
These changes are preparatory for the subsequent patches.
https://fedorahosted.org/freeipa/ticket/433
Reviewed-By: Sumit Bose <sbose@redhat.com>