ARM: dts: stm32: enable display on stm32mp157c-ev1 board

[ Upstream commit 67330599f93672bd351123c729e2591a460fd24c ]

Enable panel raydium RM68200, DSI bridge & display controller.

Signed-off-by: Yannick Fertré <yannick.fertre@st.com>
Signed-off-by: Alexandre Torgue <alexandre.torgue@st.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>