net: conn: Fix is_invalid_packet
net: conn: Fix is_invalid_packet

In switch statement break statement was missing causing IPv4 part to
execute even if the packet is IPv6. Also logical negation is wrong in
this context.

Signed-off-by: Ruslan Mstoi <348dc8e8f10581f5bc17672b9c406a6d9fcc1430@intel.com>

kraj/zephyr,GiulianoFranchetto/zephyr,galak/zephyr,Vudentz/zephyr,mbolivar/zephyr,nashif/zephyr,zephyrproject-rtos/zephyr,punitvara/zephyr,zephyriot/zephyr,GiulianoFranchetto/zephyr,explora26/zephyr,finikorg/zephyr,kraj/zephyr,GiulianoFranchetto/zephyr,ldts/zephyr,Vudentz/zephyr,mbolivar/zephyr,zephyrproject-rtos/zephyr,mbolivar/zephyr,zephyrproject-rtos/zephyr,mbolivar/zephyr,punitvara/zephyr,explora26/zephyr,nashif/zephyr,kraj/zephyr,zephyrproject-rtos/zephyr,zephyriot/zephyr,GiulianoFranchetto/zephyr,mbolivar/zephyr,finikorg/zephyr,galak/zephyr,Vudentz/zephyr,explora26/zephyr,galak/zephyr,galak/zephyr,kraj/zephyr,kraj/zephyr,nashif/zephyr,GiulianoFranchetto/zephyr,explora26/zephyr,zephyriot/zephyr,galak/zephyr,punitvara/zephyr,punitvara/zephyr,zephyriot/zephyr,finikorg/zephyr,nashif/zephyr,ldts/zephyr,finikorg/zephyr,ldts/zephyr,Vudentz/zephyr,zephyriot/zephyr,zephyrproject-rtos/zephyr,nashif/zephyr,Vudentz/zephyr,ldts/zephyr,punitvara/zephyr,ldts/zephyr,finikorg/zephyr,explora26/zephyr,Vudentz/zephyr