dts: arm: nordic: add Eng A suffix to nRF5340 CPUAPP .dtsi headers

Rename the nRF5340 QKAA variant .dtsi headers (Application
MCU) by adding an Engineering A (Eng A) suffix. This is done
to indicate that the headers should be explicitly used when
building for a board that contains the Engineeering A nrf5340
SoC variant.

Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>

boards/arm/nrf5340pdk_nrf5340/nrf5340pdk_nrf5340_cpuapp.dts

@@ -5,7 +5,7 @@
  */
 
 /dts-v1/;
-#include <nordic/nrf5340_cpuapp_qkaa.dtsi>
+#include <nordic/nrf5340_cpuapp_qkaa_eng_a.dtsi>
 #include "nrf5340pdk_nrf5340_cpuapp_common.dts"
 
 / {

boards/arm/nrf5340pdk_nrf5340/nrf5340pdk_nrf5340_cpuappns.dts

@@ -5,7 +5,7 @@
  */
 
 /dts-v1/;
-#include <nordic/nrf5340_cpuappns_qkaa.dtsi>
+#include <nordic/nrf5340_cpuappns_qkaa_eng_a.dtsi>
 #include "nrf5340pdk_nrf5340_cpuapp_common.dts"
 
 / {