ARM: dts: ste-href: Add reg property to the LP5521 channel nodes

Add the reg property to each channel node.  This update is
to accommodate the multicolor framework.  In addition to the
accommodation this allows the LEDs to be placed on any channel
and allow designs to skip channels as opposed to requiring
sequential order.

Signed-off-by: Dan Murphy <dmurphy@ti.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
CC: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20200812195020.13568-7-dmurphy@ti.com


Signed-off-by: Linus Walleij <linus.walleij@linaro.org>