lib/param: Remove special handling for 'state dir' and 'cache dir'

lib/param: Remove special handling for 'state dir' and 'cache dir'

The build system gives these two parameters different defaults
(compared with lock dir) in both the --enable-fhs and default mode, so
the logic to use lock dir no longer applies unless the build has been
very specially constructed.

Therefore, remove the special case handling and make these normal
parameters again.

Reviewed-by: Garming Sam <garming@catalyst.net.nz>
Signed-off-by: Andrew Bartlett <abartlet@samba.org>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>
Reviewed-by: Michael Adam <obnox@samba.org>