ARM: dts: stm32: Drop MMCI interrupt-names

The pl18x MMCI driver does not use the interrupt-names property,
the binding document has been updated to recommend this property
be unused, remove it.
Backport of Marek's Linux patch:
https://lore.kernel.org/linux-arm-kernel/20221013221242.218808-3-marex@denx.de/



Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Yann Gautier <yann.gautier@foss.st.com>
Signed-off-by: Marek Vasut <marex@denx.de>
Signed-off-by: Alexandre Torgue <alexandre.torgue@foss.st.com>
Signed-off-by: Yann Gautier <yann.gautier@foss.st.com>
Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com>