bind: Generate key file and correct configuration files permission
bind: Generate key file and correct configuration files permission

Base on debian/bind9.postinst, create /etc/bind/rndc.key and correct files permission in /etc/bind
which make service bind9 failed to run.

Specific path for random device to fix error when run rndc-confgen:
    You must use the keyboard to create entropy, since your system is lacking
    /dev/random (or equivalent)

Signed-off-by: Trung Do <64081e6b7eb2b24289b8a4e51cef9836ddf28af2@toshiba-tsdv.com>

nghiaht-tsdv/meta-debian,tienlee/meta-debian,meta-debian/meta-debian,tienlee/meta-debian,nghiaht-tsdv/meta-debian,meta-debian/meta-debian,nghiaht-tsdv/meta-debian,nghiaht-tsdv/meta-debian,nghiaht-tsdv/meta-debian,nghiaht-tsdv/meta-debian,tienlee/meta-debian,tienlee/meta-debian,tienlee/meta-debian,meta-debian/meta-debian,meta-debian/meta-debian,meta-debian/meta-debian,tienlee/meta-debian,meta-debian/meta-debian