qemu: driver: Don't use qemuBlockJobStartupFinalize in processBlockJobEvent

qemu: driver: Don't use qemuBlockJobStartupFinalize in processBlockJobEvent

While this function does start a block job in case when we'd not be able
to get our internal data for it, the handler sets the job state to
QEMU_BLOCKJOB_STATE_RUNNING anyways, thus qemuBlockJobStartupFinalize
would just unref the job.

Since the other usage of qemuBlockJobStartupFinalize in the other part
of the event handler was a bug replace this one anyways even if it would
not cause problems.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>