Remove other libraries not needed for RP2040

Author: oseiskar

.gitmodules

@@ -1,12 +1,3 @@
 [submodule "tools/uf2"]
 	path = tools/uf2
 	url = https://github.com/microsoft/uf2.git
-[submodule "lib/lwip"]
-	path = lib/lwip
-	url = https://github.com/lwip-tcpip/lwip.git
-[submodule "lib/FreeRTOS-Kernel"]
-	path = lib/FreeRTOS-Kernel
-	url = https://github.com/FreeRTOS/FreeRTOS-Kernel.git
-[submodule "lib/CMSIS_5"]
-	path = lib/CMSIS_5
-	url = https://github.com/ARM-software/CMSIS_5.git