Some USB peripherals draw more power, and the sourcing regulator
take a little time to turn on.  This patch fixes an issue where
some devices occasionally do not get detected, because the power
isn't quite ready when communication starts, so we add a bit
of a delay.

Fixes: 1c207f91 ("ARM: dts: imx: Add support for Logic PD i.MX6QD EVM")
Signed-off-by: Adam Ford <aford173@gmail.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>