platform: x86: MLX_PLATFORM: select REGMAP instead of depending on it

platform: x86: MLX_PLATFORM: select REGMAP instead of depending on it

[ Upstream commit 7e7e1541c91615e9950d0b96bcd1806d297e970e ]

REGMAP is a hidden (not user visible) symbol. Users cannot set it
directly thru "make *config", so drivers should select it instead of
depending on it if they need it.

Consistently using "select" or "depends on" can also help reduce
Kconfig circular dependency issues.

Therefore, change the use of "depends on REGMAP" to "select REGMAP".

Fixes: ef0f62264b2a ("platform/x86: mlx-platform: Add physical bus number auto detection")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Vadim Pasternak <vadimp@mellanox.com>
Cc: Darren Hart <dvhart@infradead.org>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Mark Gross <markgross@kernel.org>
Cc: platform-driver-x86@vger.kernel.org
Link: https://lore.kernel.org/r/20230226053953.4681-7-rdunlap@infradead.org
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>