Board-specific LWIP options for silabs boards (rs911, wf200, thread) were never used (project-chip#31929)

* Add silabs-specific lwip options to GN

* Make the lwipopts conditional

* Revert "Make the lwipopts conditional"

This reverts commit ff91e81.

* Add another dependency for lwip

Author: andy31415

src/lwip/BUILD.gn

@@ -225,6 +225,12 @@ if (current_os == "zephyr" || current_os == "mbed") {
           [ "${chip_root}/third_party/lwip/repo/lwip/src/apps/mdns/mdns.c" ]
     } else if (lwip_platform == "silabs") {
       public_deps += [ "${efr32_sdk_build_root}:efr32_sdk" ]
+
+      sources += [
+        "${lwip_platform}/lwipopts-rs911x.h",
+        "${lwip_platform}/lwipopts-thread.h",
+        "${lwip_platform}/lwipopts-wf200.h",
+      ]
     } else if (lwip_platform == "standalone") {
       public_deps += [ "${chip_root}/src/lib/support" ]
     } else if (lwip_platform == "k32w0") {

third_party/silabs/silabs_lwip/BUILD.gn

@@ -33,7 +33,12 @@ lwip_target("silabs_lwip") {
     "${chip_root}/src/lwip/silabs/lwippools.h",
   ]
 
-  sources = [ "${chip_root}/src/lwip/freertos/sys_arch.c" ]
+  sources = [
+    "${chip_root}/src/lwip/freertos/sys_arch.c",
+    "${chip_root}/src/lwip/silabs/lwipopts-rs911x.h",
+    "${chip_root}/src/lwip/silabs/lwipopts-thread.h",
+    "${chip_root}/src/lwip/silabs/lwipopts-wf200.h",
+  ]
 
   public_deps = [
     "${chip_root}/src/lwip:lwip_buildconfig",