feat(st): update STM32MP DT files

This is an alignment with Linux DT files that have been merged in
stm32 tree [1], and will be in Linux 6.7.
The /omit-if-no-ref/ in overlay files are now removed, as already in
pinctrl files.

[1] https://git.kernel.org/pub/scm/linux/kernel/git/atorgue/stm32.git

Signed-off-by: Yann Gautier <yann.gautier@st.com>
Change-Id: Iab94b0ba7a4a0288ca53d1ae57ab590566967415
diff --git a/fdts/stm32mp15xx-dhcor-som.dtsi b/fdts/stm32mp15xx-dhcor-som.dtsi
index c241efc..8d829a4 100644
--- a/fdts/stm32mp15xx-dhcor-som.dtsi
+++ b/fdts/stm32mp15xx-dhcor-som.dtsi
@@ -4,6 +4,7 @@
  * Author: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
  * Copyright (C) 2020 Marek Vasut <marex@denx.de>
  * Copyright (C) 2022 DH electronics GmbH
+ * Copyright (C) 2023, STMicroelectronics - All Rights Reserved
  */
 
 #include "stm32mp15-pinctrl.dtsi"
@@ -164,7 +165,9 @@
 
 &qspi {
 	pinctrl-names = "default";
-	pinctrl-0 = <&qspi_clk_pins_a &qspi_bk1_pins_a>;
+	pinctrl-0 = <&qspi_clk_pins_a
+		     &qspi_bk1_pins_a
+		     &qspi_cs1_pins_a>;
 	reg = <0x58003000 0x1000>, <0x70000000 0x200000>;
 	#address-cells = <1>;
 	#size-cells = <0>;