* lib/linux/libc.c: Move from lib/linux.c.
* lib/linux/gcc.c: Move from lib/linux-gcc.c.
* lib/linux/gnu.c: Move from lib/linux+gnu.c.
* lib/linux/libc.c: Move from lib/linux.c.
* lib/linux/mes.c: Move from lib/linux-mes.c.
* lib/linux/mini-gcc.c: Move from lib/linux-mini-gcc.c.
* lib/linux/mini-mes.c: Move from lib/linux-mini-mes.c.
* lib/linux/tcc.c: Move from lib/linux+tcc.c.
* lib/linux/crt0.c: Move from lib/crt0.c.
* lib/linux/crt1.c: Move from lib/crt1.c.
* lib/linux/crti.c: Move from lib/crti.c.
* lib/linux/crtn.c: Move from lib/crtn.c.
* build-aux/build-cc.sh: Update for new layout.
* build-aux/build-cc32.sh: Likewise.
* build-aux/build-mes.sh: Likewise.
* build-aux/cc-mes.sh: Likewise.
* build-aux/cc32-mes.sh: Likewise.
* lib/string/argz-count.c: New file taken from GNU C Library,
relicensed.
* lib/string/argz-extract.c: New file taken from GNU C Library,
relicensed.
* include/argz.h: New file.
* lib/string/memcpy.c: New file, extract from libc.
* lib/assert/assert.c: Likewise.
* lib/linux+gnu.c (getpid, signal): New function.
* include/signal.h: Declare signal.
* include/unistd.h: Declare getpid.
* scaffold/tests/95-signal.c: Test it.
* build-aux/check-mescc.sh (tests): Run it.