Fix CHIPConfig.h not including InetConfig.h.

We had various things that were testing config bits that InetConfig.h would pull
in that never actually included InetConfig.h, because CHIPConfig.h did not
include it.

src/lib/core/BUILD.gn

@@ -75,6 +75,7 @@ source_set("chip_config_header") {
   public_deps = [
     ":chip_buildconfig",
     "${chip_root}/src/ble:ble_config_header",
+    "${chip_root}/src/inet:inet_config_header",
     "${chip_root}/src/system:system_config_header",
   ]
 

src/lib/core/CHIPConfig.h

@@ -42,8 +42,8 @@
 #include <ble/BleConfig.h>
 #include <system/SystemConfig.h>
 
-/* COMING SOON: making the INET Layer optional entails making this inclusion optional. */
-// #include "InetConfig.h"
+#include <inet/InetConfig.h>
+
 /*
 #if INET_CONFIG_ENABLE_TCP_ENDPOINT && INET_TCP_IDLE_CHECK_INTERVAL <= 0
 #error "chip SDK requires INET_TCP_IDLE_CHECK_INTERVAL > 0"