Add missing configure option

Resolves: rhbz#1889386

realmd.spec

@@ -1,6 +1,6 @@
 Name:    realmd
 Version: 0.17.0
-Release: 4%{?dist}
+Release: 5%{?dist}
 Summary: Kerberos realm enrollment service
 License: LGPLv2+
 URL:     https://gitlab.freedesktop.org/realmd/realmd
@@ -49,7 +49,12 @@ applications that use %{name}.
 
 %build
 autoreconf -fi
-%configure --disable-silent-rules
+%configure --disable-silent-rules \
+%if 0%{?rhel}
+    --with-vendor-error-message='Please check\n    https://red.ht/support_rhel_ad \nto get help for common issues.' \
+%endif
+    %{nil}
+
 make %{?_smp_mflags}
 
 %check
@@ -80,6 +85,10 @@ make install DESTDIR=%{buildroot}
 %doc ChangeLog
 
 %changelog
+* Tue Apr 06 2021 Sumit Bose <sbose@redhat.com> - 0.17.0-5
+- Add missing configure option
+  Resolves: rhbz#1889386
+
 * Tue Apr 06 2021 Sumit Bose <sbose@redhat.com> - 0.17.0-4
 - Add vendor error message, autoconf-2.71 fixes, downstream gating
   Resolves: rhbz#1889386