net: tcp2: Do not access freed TCP connection in tcp_conn_unref()
net: tcp2: Do not access freed TCP connection in tcp_conn_unref()

Fix a potentially problematic access of the slab's data
after the slab was freed.

Signed-off-by: Oleg Zhurakivskyy <cdb82bfa180f8df716a77d2c2557196a597a233c@intel.com>

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