ddiskit.spec: replace genisoimage requirement with /usr/bin/mkisofs one

xorriso provides a drop-in mkisofs version, so let's enable usage
of either implementation by requiring a specific executable,
rather than a package.

Resolves: #1951338
Signed-off-by: Eugene Syromiatnikov <esyr@redhat.com>

ddiskit.spec

@@ -11,7 +11,7 @@ Version:        3.6
 
 %forgemeta
 
-Release:        12%{?dist}
+Release:        13%{?dist}
 Summary:        Tool for Red Hat Enterprise Linux Driver Update Disk creation
 
 License:        GPLv3
@@ -22,7 +22,8 @@ BuildArch:      noarch
 BuildRequires:  python3-devel
 BuildRequires:  python3-setuptools
 
-Requires:       rpm createrepo genisoimage
+Requires:       rpm createrepo
+Requires:       /usr/bin/mkisofs
 Suggests:       quilt git
 Recommends:     kernel-devel redhat-rpm-config rpm-build
 Recommends:     mock
@@ -67,6 +68,10 @@ find %{buildroot} -size 0 -delete
 %config(noreplace) /etc/ddiskit.config
 
 %changelog
+* Thu Apr 29 2021 Eugene Syromiatnikov <esyr@redhat.com> - 3.6-13
+- Change "Requires: genisoimage" dependency to "Requires: /usr/bin/mkisofs"
+  to enable xorriso-provided drop-in replacement implementation usage.
+
 * Thu Apr 15 2021 Mohan Boddu <mboddu@redhat.com> - 3.6-12
 - Rebuilt for RHEL 9 BETA on Apr 15th 2021. Related: rhbz#1947937