spec: Require Fedora 31

Fedora 30 has been EOL for almost a month now.
Signed-off-by: NAndrea Bolognani <abologna@redhat.com>
Reviewed-by: NPavel Hrdina <phrdina@redhat.com>

libvirt.spec.in

@@ -4,7 +4,7 @@
 # that's still supported by the vendor. It may work on other distros
 # or versions, but no effort will be made to ensure that going forward.
 %define min_rhel 7
-%define min_fedora 30
+%define min_fedora 31
 
 %if (0%{?fedora} && 0%{?fedora} >= %{min_fedora}) || (0%{?rhel} && 0%{?rhel} >= %{min_rhel})
     %define supported_platform 1

mingw-libvirt.spec.in

@@ -3,7 +3,7 @@
 # This spec file assumes you are building on a Fedora version
 # that's still supported by the vendor. It may work on other distros
 # or versions, but no effort will be made to ensure that going forward.
-%define min_fedora 30
+%define min_fedora 31
 
 %if 0%{?fedora} && 0%{?fedora} >= %{min_fedora}
     %define supported_platform 1