Docs/kernel-parameters: Add earlycon devicetree usage

This form of the earlycon parameter was added by commit fb11ffe74c794a5
("of/fdt: add FDT serial scanning for earlycon") without documentation.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
1 file changed