Bluetooth: L2CAP: Document cases where -EAGAIN is returned
Bluetooth: L2CAP: Document cases where -EAGAIN is returned

This documents the special cases where -EAGAIN is returned which leads
the buffer to be queued.

Signed-off-by: Luiz Augusto von Dentz <8530c5ea66a1bdbc08f98bfcf183c8be901b5990@intel.com>

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