Remove %clean section

None of currently supported distributions need that.
Last one was EL5 which is EOL for a while.

Signed-off-by: Igor Gnatenko <ignatenkobrain@fedoraproject.org>

zbar.spec

@@ -102,9 +102,6 @@ find ${RPM_BUILD_ROOT} -name '*.la' -or -name '*.a' | xargs rm -f
 # Remove installed doc
 rm -rf $RPM_BUILD_ROOT/usr/share/doc/zbar-%{version}/
 
-%clean
-rm -rf $RPM_BUILD_ROOT
-
 %post -p /sbin/ldconfig
 
 %post devel -p /sbin/ldconfig