MAINTAINERS: power: supply: max17042: add entry with reviewers

The Maxim max17042 fuel gauge driver supports several devices used on
multiple different boards - both devicetree and ACPI based.  The driver
is incomplete and has few known issues.  Fixing these might break other
platforms so mention recent contributors who can provide feedback.  This
way most of interested parties might help reviewing the patches.

Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Reviewed-by: Sebastian Krzyszkowiak <sebastian.krzyszkowiak@puri.sm>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>