kconfig: fix dt_node_has_prop and add nodelabel functions

The Kconfig function "dt_node_has_prop" was using label as its
parameter, where other functions use either chosen or path.
The documentation says that the parameter is path, so this patch
makes the function as documentation says and as other functions
in the file.
The additional nodelabel functions were added as counterparts that
are using nodes labels instead of paths.

Signed-off-by: Michał Barnaś <mb@semihalf.com>
5 files changed