I'm only aware of how to disable the web access, as documented in this KB.
Disabling the vSphere Web Access service in vCenter Server
http://kb.vmware.com/kb/1009420
It may not be about disabling SSL, but might get you pointed in the right direction.
VCDX #104 (DCV, NV) ஃ WahlNetwork.com ஃ @ChrisWahl ஃ Author, Networking for VMware Administrators