phy: amlogic: meson-axg-mipi-pcie-analog: replace DSI_LANE definitions with BIT() macro

For consistency, replace DSI_LANE definitions with BIT() macro and remove the unused
DSI_LANE_MASK definition.

Suggested-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lore.kernel.org/r/20201120150347.3914901-1-narmstrong@baylibre.com


Signed-off-by: Vinod Koul <vkoul@kernel.org>