Bluetooth: L2CAP: fix use of Z_STRUCT_SECTION_ITERABLE
Bluetooth: L2CAP: fix use of Z_STRUCT_SECTION_ITERABLE

Two sections are needed: bt_l2cap_fixed_chan and bt_l2cap_br_fixed_chan.
However the second one cannot be created using #define as the
preprocessor will expand it to the first before compilation happens,
sending bt_l2cap_br_fixed_chan instances in the wrong section.

This fixes commit 4e8ddfd640f9 ("Bluetooth: L2CAP: Make use of
Z_STRUCT_SECTION_ITERABLE").

Signed-off-by: Nicolas Pitre <76342682d5afc62854e1102d9578521fe1ed6813@baylibre.com>

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