uselib: default depending if libc5 was used

uselib hasn't been used since libc5; glibc does not use it.  Deprecate
uselib a bit more, by making the default y only if libc5 was widely used
on the plaform.

This makes arm64 kernel built with defconfig slightly smaller

bloat-o-meter:
  add/remove: 0/3 grow/shrink: 0/2 up/down: 0/-1390 (-1390)
  function                                     old     new   delta
  kernel_config_data                         18164   18162      -2
  uselib_flags                                  20       -     -20
  padzero                                      216     192     -24
  sys_uselib                                   380       -    -380
  load_elf_library                             964       -    -964
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

init/Kconfig

@@ -285,7 +285,7 @@ config FHANDLE
 
 config USELIB
 	bool "uselib syscall"
-	default y
+	def_bool ALPHA || M68K || SPARC || X86_32 || IA32_EMULATION
 	help
 	  This option enables the uselib syscall, a system call used in the
 	  dynamic linker from libc5 and earlier.  glibc does not use this