ARM: imx6q: drop of_platform_default_populate() from init_machine

Dropping the machine_init specific of_platform_default_populate() can be
done safely due to the following two facts:

1)
Since commit 44a7185c ("of/platform: Add common method to populate
default bus") we have a common method to populate the devices.

2)
The machine_init code don't need bounded devices<>drivers since the code
uses syscon_regmap_lookup_by_compatible() which register a syscon
device on demand.
Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm/mach-imx/mach-imx6q.c

@@ -172,9 +172,6 @@ static void __init imx6q_init_machine(void)
 				imx_get_soc_revision());
 
 	imx6q_enet_phy_init();
-
-	of_platform_default_populate(NULL, NULL, NULL);
-
 	imx_anatop_init();
 	cpu_is_imx6q() ?  imx6q_pm_init() : imx6dl_pm_init();
 	imx6q_1588_init();