Use __FREERTOS for example CI builds

Author: earlephilhower

cores/rp2040/freertos/FreeRTOS.h

@@ -1,3 +1,5 @@
 #ifdef __FREERTOS
 #include "../../../FreeRTOS-Kernel/include/FreeRTOS.h"
+#else
+#error "#define __FREERTOS 1 to use FreeRTOS in your application"
 #endif

libraries/lwIP_Ethernet/src/LwipIntfDev.h

@@ -46,8 +46,10 @@
 #include "LwipEthernet.h"
 #include "wl_definitions.h"
 
+#ifdef __FREERTOS
 #include "FreeRTOS.h"
 #include "semphr.h"
+#endif
 
 #ifndef DEFAULT_MTU
 #define DEFAULT_MTU 1500

libraries/rp2040/examples/Multicore-FreeRTOS/Multicore-FreeRTOS.ino renamed to libraries/rp2040/examples/FreeRTOS-Multicore/FreeRTOS-Multicore.ino

@@ -74,6 +74,8 @@ def compile(tmp_dir, sketch, cache, tools_dir, hardware_dir, ide_path, f, args):
             fqbn = fqbn + ",ipbtstack=ipv4btcble"
         if '/Profiling' in sketch:
             fqbn = fqbn + ",profile=Enabled"
+        if '/FreeRTOS' in sketch:
+            fqbn = fqbn + ",os=freertos"
     if '/FreeRTOS' in sketch:
         fqbn = fqbn + ",os=freertos"
     cmd += [fqbn]