ARM: dts: stm32: fix i2c node name on stm32f746 to prevent warnings

stable inclusion
from stable-5.10.53
commit 6a7af634781088be5ce9b673af487f2337f0cb90
bugzilla: 175574 https://gitee.com/openeuler/kernel/issues/I4DTUX

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=6a7af634781088be5ce9b673af487f2337f0cb90



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[ Upstream commit ad0ed10b ]

Replace upper case by lower case in i2c nodes name.

Signed-off-by: Alexandre Torgue <alexandre.torgue@foss.st.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Chen Jun <chenjun102@huawei.com>
Acked-by: Weilong Chen <chenweilong@huawei.com>
Signed-off-by: Chen Jun <chenjun102@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>