dts: arm: st: stm32wl: include <mem.h> from series' root DTSI

Include <mem.h> from the series' root DTSI file and remove inclusion of
the file from other levels since it becomes redundant. This avoids the
current situation where the same #include directive is duplicated among
many files, and where the file is sometimes included multiple times when
walking up the inclusion chain up until the root DTSI file.

Signed-off-by: Mathieu Choplain <mathieu.choplain-ext@st.com>
diff --git a/dts/arm/st/wl/stm32wl.dtsi b/dts/arm/st/wl/stm32wl.dtsi
index 3f5fd71..1544e96 100644
--- a/dts/arm/st/wl/stm32wl.dtsi
+++ b/dts/arm/st/wl/stm32wl.dtsi
@@ -17,6 +17,7 @@
 #include <zephyr/dt-bindings/reset/stm32wb_l_reset.h>
 #include <zephyr/dt-bindings/power/stm32_pwr.h>
 #include <freq.h>
+#include <mem.h>
 
 / {
 	chosen {
diff --git a/dts/arm/st/wl/stm32wl54Xc.dtsi b/dts/arm/st/wl/stm32wl54Xc.dtsi
index a7c64b9..bb50ec4 100644
--- a/dts/arm/st/wl/stm32wl54Xc.dtsi
+++ b/dts/arm/st/wl/stm32wl54Xc.dtsi
@@ -3,7 +3,6 @@
  *
  * SPDX-License-Identifier: Apache-2.0
  */
-#include <mem.h>
 #include <st/wl/stm32wl55.dtsi>
 
 / {
diff --git a/dts/arm/st/wl/stm32wl55Xc.dtsi b/dts/arm/st/wl/stm32wl55Xc.dtsi
index 7c32ca4..573e575 100644
--- a/dts/arm/st/wl/stm32wl55Xc.dtsi
+++ b/dts/arm/st/wl/stm32wl55Xc.dtsi
@@ -3,7 +3,6 @@
  *
  * SPDX-License-Identifier: Apache-2.0
  */
-#include <mem.h>
 #include <st/wl/stm32wl55.dtsi>
 
 / {
diff --git a/dts/arm/st/wl/stm32wle4X8.dtsi b/dts/arm/st/wl/stm32wle4X8.dtsi
index 925c00a..70a6fec 100644
--- a/dts/arm/st/wl/stm32wle4X8.dtsi
+++ b/dts/arm/st/wl/stm32wle4X8.dtsi
@@ -3,7 +3,6 @@
  *
  * SPDX-License-Identifier: Apache-2.0
  */
-#include <mem.h>
 #include <st/wl/stm32wle5.dtsi>
 
 / {
diff --git a/dts/arm/st/wl/stm32wle4Xb.dtsi b/dts/arm/st/wl/stm32wle4Xb.dtsi
index 9567980..b582330 100644
--- a/dts/arm/st/wl/stm32wle4Xb.dtsi
+++ b/dts/arm/st/wl/stm32wle4Xb.dtsi
@@ -3,7 +3,6 @@
  *
  * SPDX-License-Identifier: Apache-2.0
  */
-#include <mem.h>
 #include <st/wl/stm32wle5.dtsi>
 
 / {
diff --git a/dts/arm/st/wl/stm32wle4Xc.dtsi b/dts/arm/st/wl/stm32wle4Xc.dtsi
index 2b47872..5920be0 100644
--- a/dts/arm/st/wl/stm32wle4Xc.dtsi
+++ b/dts/arm/st/wl/stm32wle4Xc.dtsi
@@ -3,7 +3,6 @@
  *
  * SPDX-License-Identifier: Apache-2.0
  */
-#include <mem.h>
 #include <st/wl/stm32wle5.dtsi>
 
 / {
diff --git a/dts/arm/st/wl/stm32wle5X8.dtsi b/dts/arm/st/wl/stm32wle5X8.dtsi
index 925c00a..70a6fec 100644
--- a/dts/arm/st/wl/stm32wle5X8.dtsi
+++ b/dts/arm/st/wl/stm32wle5X8.dtsi
@@ -3,7 +3,6 @@
  *
  * SPDX-License-Identifier: Apache-2.0
  */
-#include <mem.h>
 #include <st/wl/stm32wle5.dtsi>
 
 / {
diff --git a/dts/arm/st/wl/stm32wle5Xb.dtsi b/dts/arm/st/wl/stm32wle5Xb.dtsi
index 9567980..b582330 100644
--- a/dts/arm/st/wl/stm32wle5Xb.dtsi
+++ b/dts/arm/st/wl/stm32wle5Xb.dtsi
@@ -3,7 +3,6 @@
  *
  * SPDX-License-Identifier: Apache-2.0
  */
-#include <mem.h>
 #include <st/wl/stm32wle5.dtsi>
 
 / {
diff --git a/dts/arm/st/wl/stm32wle5Xc.dtsi b/dts/arm/st/wl/stm32wle5Xc.dtsi
index 2b47872..5920be0 100644
--- a/dts/arm/st/wl/stm32wle5Xc.dtsi
+++ b/dts/arm/st/wl/stm32wle5Xc.dtsi
@@ -3,7 +3,6 @@
  *
  * SPDX-License-Identifier: Apache-2.0
  */
-#include <mem.h>
 #include <st/wl/stm32wle5.dtsi>
 
 / {