leds-gpio : Enable ldo at leds-gpio.c when booting

Add gpio_led_suspend and gpio_led_resume function
to enable and disable ldo when devices suspend and
resume.And add enable ldo function when booting.

Change-Id: I12b0dc79049e209fba641d5238a1830e7707a665
Signed-off-by: c_xlin <xlin@codeaurora.org>