[project][virtual][fs] add fat32 driver to the default fs build
[project][virtual][fs] add fat32 driver to the default fs build

travisg/lk,littlekernel/lk,minglun-tsai/lk,hollanderic/lkstuff,travisg/lk,littlekernel/lk,travisg/lk,littlekernel/lk,minglun-tsai/lk,minglun-tsai/lk,hollanderic/lkstuff,minglun-tsai/lk,hollanderic/lkstuff,travisg/lk,hollanderic/lkstuff,littlekernel/lk