coreutils: Move stdbuf into an own package coreutils-stdbuf

The coreutils implementation of stdbuf uses LD_PRELOAD
to dynamically load libstdbuf which calls setvbuf().
This can't be implemented simply in busybox since it produces
one or two statically linked executables. Therefore, stdbuf
should be packaged separately for people who are using busybox
instead of coreutils for the other tools.

coreutils depends on the new package,
so nothing changes when installing coreutils.

(From OE-Core rev: 992cec44ad2073cfe05cb2c58936032af189748a)

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-core/coreutils/coreutils_8.31.bb

@@ -49,7 +49,7 @@ bindir_progs = "arch basename chcon cksum comm csplit cut dir dircolors dirname
                 env expand expr factor fmt fold groups head hostid id install \
                 join link logname md5sum mkfifo nl nohup nproc od paste pathchk \
                 pinky pr printf ptx readlink realpath runcon seq sha1sum sha224sum sha256sum \
-                sha384sum sha512sum shred shuf sort split stdbuf sum tac tail tee test timeout \
+                sha384sum sha512sum shred shuf sort split sum tac tail tee test timeout \
                 tr truncate tsort tty unexpand uniq unlink uptime users vdir wc who whoami yes"
 
 # hostname gets a special treatment and is not included in this
@@ -58,6 +58,10 @@ base_bindir_progs = "cat chgrp chmod chown cp date dd echo false hostname kill l
 
 sbindir_progs= "chroot"
 
+PACKAGE_BEFORE_PN_class-target += "coreutils-stdbuf"
+FILES_coreutils-stdbuf = "${bindir}/stdbuf ${libdir}/coreutils/libstdbuf.so"
+RDEPENDS_coreutils_class-target += "coreutils-stdbuf"
+
 # Let aclocal use the relative path for the m4 file rather than the
 # absolute since coreutils has a lot of m4 files, otherwise there might
 # be an "Argument list too long" error when it is built in a long/deep