ARM: dts: stm32mp1: DT alignment with kernel v5.4

Device tree and binding alignment with kernel v5.4

Signed-off-by: Patrick Delaunay <patrick.delaunay@st.com>
Reviewed-by: Patrice Chotard <patrice.chotard@st.com>
diff --git a/arch/arm/dts/stm32mp157-pinctrl.dtsi b/arch/arm/dts/stm32mp157-pinctrl.dtsi
index 0d53396..07cd080 100644
--- a/arch/arm/dts/stm32mp157-pinctrl.dtsi
+++ b/arch/arm/dts/stm32mp157-pinctrl.dtsi
@@ -622,13 +622,13 @@
 						 <STM32_PINMUX('F', 6, AF9)>; /* QSPI_BK1_IO3 */
 					bias-disable;
 					drive-push-pull;
-					slew-rate = <3>;
+					slew-rate = <1>;
 				};
 				pins2 {
 					pinmux = <STM32_PINMUX('B', 6, AF10)>; /* QSPI_BK1_NCS */
 					bias-pull-up;
 					drive-push-pull;
-					slew-rate = <3>;
+					slew-rate = <1>;
 				};
 			};
 
@@ -650,13 +650,13 @@
 						 <STM32_PINMUX('G', 7, AF11)>; /* QSPI_BK2_IO3 */
 					bias-disable;
 					drive-push-pull;
-					slew-rate = <3>;
+					slew-rate = <1>;
 				};
 				pins2 {
 					pinmux = <STM32_PINMUX('C', 0, AF10)>; /* QSPI_BK2_NCS */
 					bias-pull-up;
 					drive-push-pull;
-					slew-rate = <3>;
+					slew-rate = <1>;
 				};
 			};