rules: only export a single function Really all we need from this file is a way to get xkb_component_names from an xkb_rule_names, which is now the only thing being exposed. This should allow for some much needed refactoring of this code. Since this is only used by xkbcomp.c and uses xkbcomp functions, also move rules.{c,h} under the xkbcomp dir. Signed-off-by: Ran Benita <ran234@gmail.com>