[tools] cmake-clang compatible with bsp that does not support C++.
[tools] cmake-clang compatible with bsp that does not support C++.

hezlog/rt-thread,hezlog/rt-thread,RT-Thread/rt-thread,geniusgogo/rt-thread,geniusgogo/rt-thread,hezlog/rt-thread,geniusgogo/rt-thread,hezlog/rt-thread,RT-Thread/rt-thread,RT-Thread/rt-thread,nongxiaoming/rt-thread,nongxiaoming/rt-thread,RT-Thread/rt-thread,geniusgogo/rt-thread,nongxiaoming/rt-thread,nongxiaoming/rt-thread,hezlog/rt-thread,nongxiaoming/rt-thread,hezlog/rt-thread,geniusgogo/rt-thread,nongxiaoming/rt-thread,RT-Thread/rt-thread,geniusgogo/rt-thread,geniusgogo/rt-thread,nongxiaoming/rt-thread,RT-Thread/rt-thread,RT-Thread/rt-thread,hezlog/rt-thread