spec: Update Fedora minimum supported version

Fedora 29 has reached its end of life on November 26th 2019.

For more info, please, refer to the following e-mail:
https://lists.fedoraproject.org/archives/list/devel-announce@lists.fedoraproject.org/thread/Signed-off-by: NFabiano Fidêncio <fidencio@redhat.com>
Reviewed-by: NDaniel P. Berrangé <berrange@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 29
+%define min_fedora 30
 
 %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 29
+%define min_fedora 30
 
 %if 0%{?fedora} && 0%{?fedora} >= %{min_fedora}
     %define supported_platform 1