Added unset __STRICT_ANSI__ for MinGW
Added unset __STRICT_ANSI__ for MinGW

On MinGW when you set something to -std=c99 it sets __STRICT_ANSI__
which does not work with a lot of deps on clibs. So we need to turn it
off.

georgy7/clib-win32,clibs/clib,ZJU-Shaonian-Biancheng-Tuan/clib,clibs/clib,clibs/clib,zyoung51/clib,zyoung51/clib,ZJU-Shaonian-Biancheng-Tuan/clib,eejackliu/clib,clibs/clib,eejackliu/clib,zyoung51/clib,FelixZhang00/clib,zyoung51/clib,georgy7/clib-win32,FelixZhang00/clib,0dayZh/clib,0dayZh/clib