ARM: restart: allow platforms more flexibility specifying restart mode

Change 'soft_reboot' into a more generic 'restart_mode' variable,
allowing the default restart mode to be specified.

Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/kernel/setup.c

@@ -902,8 +902,8 @@ void __init setup_arch(char **cmdline_p)
 	machine_desc = mdesc;
 	machine_name = mdesc->name;
 
-	if (mdesc->soft_reboot)
-		reboot_setup("s");
+	if (mdesc->restart_mode)
+		reboot_setup(&mdesc->restart_mode);
 
 	init_mm.start_code = (unsigned long) _text;
 	init_mm.end_code   = (unsigned long) _etext;