Bluetooth: Host: Remove unused function att_chan_is_connected()
Bluetooth: Host: Remove unused function att_chan_is_connected()

gcc does not warn on unused static inline functions.

Signed-off-by: Herman Berget <22d956f84c179c5c22821e4925fbb7a703726077@nordicsemi.no>

galak/zephyr,finikorg/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,galak/zephyr,galak/zephyr,finikorg/zephyr,zephyrproject-rtos/zephyr,finikorg/zephyr,galak/zephyr,finikorg/zephyr,zephyrproject-rtos/zephyr,galak/zephyr,finikorg/zephyr,zephyrproject-rtos/zephyr