distro/redhat: build needs pkg-config and nhrpd needs c-ares
diff --git a/redhat/quagga.spec.in b/redhat/quagga.spec.in
index ba1eb19..0e2306e 100644
--- a/redhat/quagga.spec.in
+++ b/redhat/quagga.spec.in
@@ -121,7 +121,7 @@
 Requires(preun): /sbin/install-info
 Requires(post):	/sbin/install-info
 BuildRequires:	texi2html texinfo autoconf patch libcap-devel groff
-BuildRequires:  perl-generators
+BuildRequires:  perl-generators pkgconfig
 %if %{with_snmp}
 BuildRequires:	net-snmp-devel
 Requires:		net-snmp
@@ -134,6 +134,10 @@
 BuildRequires:	pam-devel
 Requires:		pam
 %endif
+%if %{with_nhrpd}
+BuildRequires:	c-ares-devel
+Requires:	c-ares
+%endif
 %if "%{initsystem}" == "systemd"
 BuildRequires:		systemd
 Requires(post):		systemd