* elf/Makefile (distribute): Add dl-osinfo.h.
* sysdeps/generic/dl-osinfo.h: New file.
* sysdeps/unix/sysv/linux/dl-osinfo.h: New file.
* sysdeps/generic/dl-sysdep.c (_dl_sysdep_start): Use DL_SYSDEP_OSCHECK
if defined.
* sysdeps/unix/sysv/linux/init-first.c: Perform kernel version test
only for !SHARED case. Get the code from dl-osinfo.h.
