spec: Add the build dependency of make

For some minimal OS like fedora cloud image, the make is not installed
by default.
Signed-off-by: NHan Han <hhan@redhat.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>

libvirt.spec.in

@@ -269,6 +269,7 @@ BuildRequires: python36-docutils
 BuildRequires: python3-docutils
 %endif
 BuildRequires: gcc
+BuildRequires: make
 BuildRequires: git
 %if 0%{?fedora} || 0%{?rhel} > 7
 BuildRequires: perl-interpreter