samples: console: echo: Be sure to print (both) CR LF in messages
samples: console: echo: Be sure to print (both) CR LF in messages

As it stands now, the console effectively works in raw mode, so all
messages should end with "\r\n". This was missed previously, because
the sample was run in QEMU, on top of POSIX cooked console. Running
on real hardware showed this issue.

Signed-off-by: Paul Sokolovsky <35cb557f011771c94f127d6fef99f804b62203f5@linaro.org>

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