Make devel sub-package requiring architecture

xosd.spec

@@ -24,7 +24,7 @@ the effect of an On Screen Display, like your TV/VCR etc.
 %package        devel
 Summary:        Development files for the XOSD on-screen display library
 Group:          Development/Libraries
-Requires:       %{name} = %{version}-%{release}
+Requires:       %{name}%{?_isa} = %{version}-%{release}
 Requires:       libX11-devel
 Requires:       libXext-devel
 Requires:       libXinerama-devel