building.py: add clang static analyzer support
building.py: add clang static analyzer support

It adds the '--clang-analyzer' option that could invoke clang as the
static code checker. It is recommanded to work with 'scan-build' shipped
with Clang. For example, `scan-build scons --clang-analyzer`.

igou/rt-thread,armink/rt-thread,AubrCool/rt-thread,wolfgangz2013/rt-thread,weiyuliang/rt-thread,igou/rt-thread,hezlog/rt-thread,yongli3/rt-thread,igou/rt-thread,weety/rt-thread,yongli3/rt-thread,RT-Thread/rt-thread,weety/rt-thread,RT-Thread/rt-thread,geniusgogo/rt-thread,geniusgogo/rt-thread,wolfgangz2013/rt-thread,FlyLu/rt-thread,yongli3/rt-thread,zhaojuntao/rt-thread,gbcwbz/rt-thread,FlyLu/rt-thread,weety/rt-thread,wolfgangz2013/rt-thread,wolfgangz2013/rt-thread,weiyuliang/rt-thread,yongli3/rt-thread,weety/rt-thread,AubrCool/rt-thread,RT-Thread/rt-thread,weiyuliang/rt-thread,hezlog/rt-thread,armink/rt-thread,yongli3/rt-thread,RT-Thread/rt-thread,weiyuliang/rt-thread,RT-Thread/rt-thread,ArdaFu/rt-thread,AubrCool/rt-thread,geniusgogo/rt-thread,wolfgangz2013/rt-thread,ArdaFu/rt-thread,wolfgangz2013/rt-thread,zhaojuntao/rt-thread,igou/rt-thread,zhaojuntao/rt-thread,armink/rt-thread,yongli3/rt-thread,igou/rt-thread,weety/rt-thread,nongxiaoming/rt-thread,yongli3/rt-thread,zhaojuntao/rt-thread,hezlog/rt-thread,FlyLu/rt-thread,ArdaFu/rt-thread,hezlog/rt-thread,hezlog/rt-thread,igou/rt-thread,geniusgogo/rt-thread,nongxiaoming/rt-thread,nongxiaoming/rt-thread,weety/rt-thread,nongxiaoming/rt-thread,FlyLu/rt-thread,AubrCool/rt-thread,gbcwbz/rt-thread,geniusgogo/rt-thread,geniusgogo/rt-thread,gbcwbz/rt-thread,zhaojuntao/rt-thread,gbcwbz/rt-thread,armink/rt-thread,AubrCool/rt-thread,FlyLu/rt-thread,armink/rt-thread,weiyuliang/rt-thread,gbcwbz/rt-thread,ArdaFu/rt-thread,zhaojuntao/rt-thread,zhaojuntao/rt-thread,hezlog/rt-thread,nongxiaoming/rt-thread,gbcwbz/rt-thread,RT-Thread/rt-thread,ArdaFu/rt-thread,armink/rt-thread,AubrCool/rt-thread,gbcwbz/rt-thread,nongxiaoming/rt-thread,weiyuliang/rt-thread,AubrCool/rt-thread,igou/rt-thread,geniusgogo/rt-thread,FlyLu/rt-thread,FlyLu/rt-thread,ArdaFu/rt-thread,weety/rt-thread,RT-Thread/rt-thread,wolfgangz2013/rt-thread,weiyuliang/rt-thread,nongxiaoming/rt-thread,hezlog/rt-thread,ArdaFu/rt-thread,armink/rt-thread