[qyoto] only use mono_arches if defined

[Rex Dieter]

commit 89e7c6116df543ae46bf342f5054fbc7e03997fe
Author: Rex Dieter <rdieter at math.unl.edu>
Date:   Wed Apr 3 10:14:05 2013 -0500

    only use mono_arches if defined

 qyoto.spec |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/qyoto.spec b/qyoto.spec
index a99e8a1..7e7f36b 100644
--- a/qyoto.spec
+++ b/qyoto.spec
@@ -38,7 +38,7 @@ Provides: mono-qt = %{version}-%{release}
 %{?_qt4:Requires: qt4%{?_isa} >= %{_qt4_version}}
 Requires: smokeqt%{?_isa} >= %{version}
 
-ExclusiveArch: %{mono_arches}
+%{?mono_arches:ExclusiveArch: %{mono_arches}}
 
 %description
 %{summary}.