Move from using Kconfig TRACING_BACKEND_UART_NAME to a devicetree
chosen property ("zephyr,tracing-uart"). This is similar to a number
of other functions like "zephyr,shell-uart" or "zephyr,bt-uart".
Signed-off-by: Kumar Gala <galak@kernel.org>
This is more a sample than a test, so put it under samples with the goal
of having dedicated tracing tests in the future under tests.
Signed-off-by: Anas Nashif <anas.nashif@intel.com>