leds: an30259a: add a check for devm_regmap_init_i2c

leds: an30259a: add a check for devm_regmap_init_i2c

BugLink: https://bugs.launchpad.net/bugs/1860816
[ Upstream commit fc7b5028f2627133c7c18734715a08829eab4d1f ]

an30259a_probe misses a check for devm_regmap_init_i2c and may cause
problems.
Add a check and print errors like other leds drivers.

Signed-off-by: Chuhong Yuan <hslester96@gmail.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>