samples: wifi: sr_coex: Remove stale DTS overlay

This was done at the beginning as a temporary fix and is definitely not
cross-platform, so, remove it to avoid build errors for 54 Series.

Signed-off-by: Chaitanya Tata <[email protected]>
(cherry picked from commit 58cc904)

Author: krish2718

samples/wifi/ble_coex/CMakeLists.txt

@@ -6,8 +6,6 @@
 
 cmake_minimum_required(VERSION 3.20.0)
 
-set(EXTRA_DTC_OVERLAY_FILE "dts.overlay")
-
 find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
 project(nrf_wifi_sta)
 

samples/wifi/ble_coex/dts.overlay

@@ -6,8 +6,6 @@
 
 cmake_minimum_required(VERSION 3.20.0)
 
-set(EXTRA_DTC_OVERLAY_FILE "dts.overlay")
-
 find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
 project(nrf_wifi_thread_coex)