qemu: Reset all migration parameters

qemu: Reset all migration parameters

Restore the original values of all migration parameters we store in
qemuDomainJobObj instead of explicitly resting only a limited set of
them.

The result is not strictly equivalent to the previous code wrt reseting
TLS state because the previous code would only reset it if we changed it
before while the new code will reset it always if QEMU supports TLS
migration. This is not a problem for the parameters themselves, but it
can cause spurious errors about missing TLS objects being logged at the
end of non-TLS migration. This issue will be fixed ~50 patches later.

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>