alsa-state: fix pkg_postinst and set INHIBIT_UPDATERCD_BBCLASS

alsa-state: fix pkg_postinst and set INHIBIT_UPDATERCD_BBCLASS

As alsa-state inherits update-rc.d, the update-rc.d part inpostinst script
has already been handled in update-rc.d.bbclass.

Besides, we need to set INHIBIT_UPDATERCD_BBCLASS to "1" if 'sysvinit'
is not in DISTRO_FEATURES. This is because the init script is not installed
in such situation, adding update-rc.d part in the preinst/postinst scripts
just makes no sense.

(From OE-Core rev: 9b9da6667b606a56c89abc1b458f52dcca9774e9)

Signed-off-by: Chen Qi <Qi.Chen@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>