ARM: dts: stm32: fix stm32mp157c-odyssey card detect pin

ARM: dts: stm32: fix stm32mp157c-odyssey card detect pin

[ Upstream commit 0171b07373cc8c2815ca5fa79a7308fdefa54ca4 ]

The microSD card detect pin is physically connected to the MPU pin PI3.
The Device Tree configuration of the card detect pin was wrong—it was
set to pin PB7 instead. If such configuration was used, the kernel would
hang on “Waiting for root device” when booting from a microSD card.

Signed-off-by: Grzegorz Szymaszek <gszymaszek@short.pl>
Signed-off-by: Alexandre Torgue <alexandre.torgue@foss.st.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>