[QPG] Fix for OpenThread Stack bump compile issue

Author: dvdm-qorvo

third_party/openthread/platforms/qpg/BUILD.gn

@@ -62,7 +62,10 @@ source_set("libopenthread-qpg") {
     "${openthread_qpg_root}/src/${openthread_qpg_family}/uart.c",
   ]
 
-  include_dirs = [ "${openthread_qpg_root}/src/${openthread_qpg_family}" ]
+  include_dirs = [
+    "${openthread_qpg_root}/src/${openthread_qpg_family}",
+    "${openthread_root}/examples/platforms/utils",
+  ]
 
   sources += [
     "${openthread_root}/examples/apps/cli/cli_uart.cpp",