MAINTAINERS: Add ROHM BU27008

Add myself as a maintainer for ROHM BU27008 color sensor driver.

Signed-off-by: Matti Vaittinen <mazziesaccount@gmail.com>
Link: https://lore.kernel.org/r/31e25a41135ab0a86645b5078af797802b32f9c7.1683541225.git.mazziesaccount@gmail.com


Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>