rpm: add deps on rpcgen/libtirpc-devel

Since RPC support moved out of glibc we need to have explicit deps on
the new packages providing this functionality
Reviewed-by: NAndrea Bolognani <abologna@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

libvirt.spec.in

@@ -464,6 +464,11 @@ BuildRequires: wireshark-devel >= 2.1.0
 BuildRequires: libssh-devel >= 0.7.0
 %endif
 
+%if 0%{?fedora} > 27 || 0%{?rhel} > 7
+BuildRequires: rpcgen
+BuildRequires: libtirpc-devel
+%endif
+
 Provides: bundled(gnulib)
 
 %description