i2c: stm32f7: add stm32mp15 compatible

Add a new compatible "st,stm32mp15-i2c" introduced in Linux kernel v5.8

Signed-off-by: Patrick Delaunay <patrick.delaunay@st.com>
Reviewed-by: Heiko Schocher <hs@denx.de>
diff --git a/drivers/i2c/stm32f7_i2c.c b/drivers/i2c/stm32f7_i2c.c
index ada8f40..593f713 100644
--- a/drivers/i2c/stm32f7_i2c.c
+++ b/drivers/i2c/stm32f7_i2c.c
@@ -873,6 +873,7 @@
 
 static const struct udevice_id stm32_i2c_of_match[] = {
 	{ .compatible = "st,stm32f7-i2c", .data = (ulong)&stm32f7_setup },
+	{ .compatible = "st,stm32mp15-i2c", .data = (ulong)&stm32f7_setup },
 	{}
 };