ARM: sunxi: Add "allwinner,sun6i-a31s" to mach-sunxi

So far the A31s is 100% compatible with the A31, still lets do the same
as what we've done for the A13 / A10s and give it its own compatible string,
in case we need to differentiate later.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
[Maxime: Removed unusude CPU_OF_DECLARE_METHOD]
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>

Documentation/arm/sunxi/README

@@ -50,7 +50,6 @@ SunXi family
           http://dl.linux-sunxi.org/A31/A3x_release_document/A31/IC/A31%20user%20manual%20V1.1%2020130630.pdf
 
       - Allwinner A31s (sun6i)
-        + Not Supported
         + Datasheet
           http://dl.linux-sunxi.org/A31/A3x_release_document/A31s/IC/A31s%20datasheet%20V1.3%2020131106.pdf
         + User Manual

arch/arm/mach-sunxi/platsmp.c

@@ -120,4 +120,4 @@ static struct smp_operations sun6i_smp_ops __initdata = {
 	.smp_prepare_cpus	= sun6i_smp_prepare_cpus,
 	.smp_boot_secondary	= sun6i_smp_boot_secondary,
 };
-CPU_METHOD_OF_DECLARE(sun6i_smp, "allwinner,sun6i-a31", &sun6i_smp_ops);
+CPU_METHOD_OF_DECLARE(sun6i_a31_smp, "allwinner,sun6i-a31", &sun6i_smp_ops);

arch/arm/mach-sunxi/sunxi.c

@@ -29,6 +29,7 @@ MACHINE_END
 
 static const char * const sun6i_board_dt_compat[] = {
 	"allwinner,sun6i-a31",
+	"allwinner,sun6i-a31s",
 	NULL,
 };
 

drivers/clk/sunxi/clk-sunxi.c

@@ -1226,6 +1226,7 @@ static void __init sun6i_init_clocks(struct device_node *node)
 			  ARRAY_SIZE(sun6i_critical_clocks));
 }
 CLK_OF_DECLARE(sun6i_a31_clk_init, "allwinner,sun6i-a31", sun6i_init_clocks);
+CLK_OF_DECLARE(sun6i_a31s_clk_init, "allwinner,sun6i-a31s", sun6i_init_clocks);
 CLK_OF_DECLARE(sun8i_a23_clk_init, "allwinner,sun8i-a23", sun6i_init_clocks);
 
 static void __init sun9i_init_clocks(struct device_node *node)