The driver.{c,h} files are primarily targetted at loading hypervisor
drivers and some helper functions in that area. It also, however,
contains a generically useful function for loading extension modules
that is called by the storage driver. Split that functionality off
into a new virmodule.{c,h} file to isolate it.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
