arch: remove KCORE_ELF again [tile]

The Kconfig symbol KCORE_ELF was removed in v2.6.0, but reappeared in two
architectures. It is useless. Remove it again.
Signed-off-by: NPaul Bolle <pebolle@tiscali.nl>
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com> (tile only)

arch/tile/Kconfig

@@ -414,11 +414,6 @@ endmenu
 
 menu "Executable file formats"
 
-# only elf supported
-config KCORE_ELF
-	def_bool y
-	depends on PROC_FS
-
 source "fs/Kconfig.binfmt"
 
 endmenu