The newly added support for Buzz controller

- introduced Kconfig selection of LEDS_CLASS
- introduced conditional preprocessor checking for CONFIG_LEDS_CLASS

This has multiple problems -- namely select doesn't work transitively,
so it shouldn't be used. On the other hand the code assumed that LEDS_CLASS
is enabled in some places, but not everywhere.

Put LEDS_CLASS as a Kconfig dependency for hid-sony and remove all the
CONFIG_LEDS_CLASS conditionals from hid-sony.

Reported-by: fengguang.wu@intel.com
Signed-off-by: NJiri Kosina <jkosina@suse.cz>