Silence compilation warnings

Add compilation flags to silence warnings about unused functions
and parameters.

Change-Id: I2c87a39c2adc05a19a59cf3978c5612f568be61a
diff --git a/rtos/CMakeLists.txt b/rtos/CMakeLists.txt
index f86cb83..753b307 100644
--- a/rtos/CMakeLists.txt
+++ b/rtos/CMakeLists.txt
@@ -38,9 +38,14 @@
     #if ThreadX supports this configuration, build ThreadX.
     if (EXISTS ${CMAKE_CURRENT_LIST_DIR}/threadx/ports/${THREADX_ARCH}/${THREADX_TOOLCHAIN}/CMakeLists.txt)
         add_subdirectory(threadx)
+
         if(THREADX_ARCH STREQUAL "cortex_m33" OR THREADX_ARCH STREQUAL "cortex_m55")
             target_compile_definitions(threadx PUBLIC TX_SINGLE_MODE_SECURE)
         endif()
+
+        target_compile_options(threadx PRIVATE
+            -Wno-unused-function
+            -Wno-unused-parameter)
     else()
         message(STATUS "Skipping ThreadX build - doesn't support toolchain=${THREADX_TOOLCHAIN} and cpu=${THREADX_ARCH}")
     endif()