fix double %_bindir in %post scripts

alex.spec

@@ -45,10 +45,10 @@ lex or flex for C/C++.
 
 %if %{with static}
 %package common
-Summary:        Common files for alex
+Summary:        Common files for %{name}
 
 %description common
-This provides the common files for alex.
+This provides the common files for %{name}.
 
 
 %package static
@@ -102,7 +102,7 @@ rm %{buildroot}%{_pkgdocdir}/LICENSE
 %if %{with static}
 %post
 %{_sbindir}/update-alternatives --install %{_bindir}/%{name} \
-  %{name} %{_bindir}/%{_bindir}/%{name}.dynamic 70
+  %{name} %{_bindir}/%{name}.dynamic 70
 
 
 %postun
@@ -113,7 +113,7 @@ fi
 
 %post static
 %{_sbindir}/update-alternatives --install %{_bindir}/%{name} \
-  %{name} %{_bindir}/%{_bindir}/%{name}.static 30
+  %{name} %{_bindir}/%{name}.static 30
 
 
 %postun static