whack-a-mole: USE_ELF_CORE_DUMP

It's been killed off back in 2009.  Not a damn thing checks it.
Just die, already...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

arch/c6x/include/asm/elf.h

@@ -56,7 +56,6 @@ do {								\
 /* Nothing for now. Need to setup DP... */
 #define ELF_PLAT_INIT(_r)
 
-#define USE_ELF_CORE_DUMP
 #define ELF_EXEC_PAGESIZE	4096
 
 #define ELF_CORE_COPY_REGS(_dest, _regs)		\

arch/csky/include/asm/elf.h

@@ -50,7 +50,6 @@ typedef elf_greg_t elf_gregset_t[ELF_NGREG];
 /*
  * These are used to set parameters in the core dumps.
  */
-#define USE_ELF_CORE_DUMP
 #define ELF_EXEC_PAGESIZE		4096
 #define ELF_CLASS			ELFCLASS32
 #define ELF_PLAT_INIT(_r, load_addr)	{ _r->a0 = 0; }

arch/hexagon/include/asm/elf.h

@@ -181,7 +181,6 @@ do {					\
  */
 #define ELF_PLAT_INIT(regs, load_addr) do { } while (0)
 
-#define USE_ELF_CORE_DUMP
 #define CORE_DUMP_USE_REGSET
 
 /* Hrm is this going to cause problems for changing PAGE_SIZE?  */

arch/nds32/include/asm/elf.h

@@ -126,7 +126,6 @@ struct elf32_hdr;
 #define ELF_DATA	ELFDATA2LSB
 #endif
 #define ELF_ARCH	EM_NDS32
-#define USE_ELF_CORE_DUMP
 #define ELF_EXEC_PAGESIZE	PAGE_SIZE
 
 /* This is the location that an ET_DYN program is loaded if exec'ed.  Typical