cmake(enhance):add NuttX CMake extensions module

[xuxin930]

Summary

[Enhancement]

1. Wrapped CMake native method is nuttx_cmake module,
   It can be quickly called in the build system

2. Add sanity check for commonly called functions

This will make our build system simpler and more modern :-)

e.g:

# we are currently adding an application library like:
# apps/libfoo/CMakeLists.txt
if(CONFIG_LIB_FOO)
  set(FLAGS -Werror)
  set(INCDIR ${CMAKE_CURRENT_LIST_DIR}/include)

  file(GLOB CSRCS ${CMAKE_CURRENT_LIST_DIR}/*.c)
  set(CSRCS ${CSRCS})

  if(CONFIG_AAA)
    list(APPEND CSRCS a.c)
  endif()
 
  if(CONFIG_BBB)
    list(APPEND CSRCS b.c)
  endif()

  if(CONFIG_OPT)
    list(APPEND FLAGS -Os)
  endif()
  
  nuttx_add_library(foo STATIC)
  target_sources(foo PRIVATE ${CSRCS})
  target_compile_options(foo PRIVATE ${FLAGS})
  target_include_directories(foo PRIVATE ${INCDIR})

endif()

# after using the extension, it can be simplified to:
# apps/libfoo/CMakeLists.txt
nuttx_library_ifdef(CONFIG_LIB_FOO foo)

nuttx_wildcard_sources(./*.c)
nuttx_sources_ifdef(CONFIG_AAA a.c)
nuttx_sources_ifdef(CONFIG_BBB b.c)

nuttx_compile_options(-Werror)
nuttx_compile_options_ifdef(CONFIG_OPT -Os)

nuttx_include_directories(${CMAKE_CURRENT_LIST_DIR}/include)

Impact

Enhanced cmake module, forward compatibility, no impact on the past

Testing

I haven't made any module changes to use the new extensions,
but I've modified the tests in local apps and it's feasible.
It greatly reduces the amount of code and is elegant enough.