Split out the current function in order to share the code with hostdev
in a future patch. Failure to match the expected sgio value against what
is stored will cause an error which the caller would need to handle since
only the caller has the disk (or eventually hostdev) specific data in
order to uniquely identify the disk in an error message.
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>