leds: pm8058: add device tree bindings

This adds the device tree bindings for the PM8058 LEDs.

Cc: devicetree@vger.kernel.org
Cc: linux-arm-msm@vger.kernel.org
Cc: Andy Gross <andy.gross@linaro.org>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>