Commit 21ad56e9 introduced a regression where a VM with a corrupted
save image file would fail to start on the first attempt. This was
caused by returning a wrong return code as 'fd' was abused to also hold
the return code.

Since it's easy to miss this nuance, introduce a 'ret' variable for the
return code and return it' value in the error section.

https://bugzilla.redhat.com/show_bug.cgi?id=1791522Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NPavel Mores <pmores@redhat.com>