earlycon: initialise baud field of earlycon device structure

For now baud field of earlycon structure device is't initialised at all
in of_setup_earlycon (in oppositе to register_earlycon).

So when I use stdout-path to point earlycon device
(like stdout-path = &serial or stdout-path = "serial:115200n8")
baud field of earlycon device structure remains uninitialised and
earlycon initialization is not performed correctly as
of_setup_earlycon is used.
When pass all arguments via bootargs
(like bootargs = "earlycon=uart8250,mmio32,0xf0005000,115200n8")
initialization is performed correctly as register_earlycon is used.

So initialise baud field of earlycon device structure by value of
"current-speed" property from device tree or from options
(if they exist) when we use of_setup_earlycon
Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/earlycon.c

@@ -282,7 +282,12 @@ int __init of_setup_earlycon(const struct earlycon_id *match,
 		}
 	}
 
+	val = of_get_flat_dt_prop(node, "current-speed", NULL);
+	if (val)
+		early_console_dev.baud = be32_to_cpu(*val);
+
 	if (options) {
+		early_console_dev.baud = simple_strtoul(options, NULL, 0);
 		strlcpy(early_console_dev.options, options,
 			sizeof(early_console_dev.options));
 	}