Updates device tree pin states definitions and node
descriptions to group pins sharing common properties.
Accordingly, updates in-tree overlays as well.
Signed-off-by: Glauber Maroto Ferreira <glauber.ferreira@espressif.com>
Add overlay for espressif boards that does not have a built-in LED.
Add instructions on README file about the required LED connection.
Signed-off-by: Lucas Tamborrino <lucas.tamborrino@espressif.com>