This backs out a part of PR 1179 which has a very serious error: If C buffered I/O is available, then printf() and vprintf MUST use it. Otherwise, the ordering of the I/O will be screwed up. They must not use direct file descriptor I/O UNLESS C buffered I/O is disabled.
Squashed commit of the following:
libs/libxx: Fix some confusing in naming. If the directory is called libxx, then the library must be libxx.a (unless perhaps LIBCXX is selected).
libs/: Fix paths in moved library directories.
libs: Brute force move of libc, libnx, and libxx to libs. Cannot yet build it in that configuration.
