蓝牙pincode设置

在/usr/var/lib/bluetooth/xx:xx:xx:xx:xx:xx/pincode里记录每个设备的pincode
格式如下：
00:03:89:AB:4D:9B 0000
00:19:86:00:38:0C 0000

注意：需要把/etc/bluetooth/hcid.conf 里的 security 设置为 auto
options {
# Automatically initialize new devices
autoinit yes;

# Security Manager mode
# none - Security manager disabled
# auto - Use local PIN for incoming connections
# user - Always ask user for a PIN
#
security auto;

# Pairing mode
# none - Pairing disabled
# multi - Allow pairing with already paired devices
# once - Pair once and deny successive attempts
pairing multi;
}