frv: don't offer BINFMT_FLAT

Fix the following compile error:

  CC      fs/binfmt_flat.o
In file included from
/home/bunk/linux/kernel-2.6/git/linux-2.6/fs/binfmt_flat.c:36:
/home/bunk/linux/kernel-2.6/git/linux-2.6/include/linux/flat.h:14:22: error: asm/flat.h: No such file or directory
/home/bunk/linux/kernel-2.6/git/linux-2.6/fs/binfmt_flat.c: In function 'create_flat_tables':
/home/bunk/linux/kernel-2.6/git/linux-2.6/fs/binfmt_flat.c:124: error: implicit declaration of function 'flat_stack_align'
/home/bunk/linux/kernel-2.6/git/linux-2.6/fs/binfmt_flat.c:125: error: implicit declaration of function 'flat_argvp_envp_on_stack'
/home/bunk/linux/kernel-2.6/git/linux-2.6/fs/binfmt_flat.c: In function 'calc_reloc':
/home/bunk/linux/kernel-2.6/git/linux-2.6/fs/binfmt_flat.c:347: error: implicit declaration of function 'flat_reloc_valid'
/home/bunk/linux/kernel-2.6/git/linux-2.6/fs/binfmt_flat.c: In function 'load_flat_file':
/home/bunk/linux/kernel-2.6/git/linux-2.6/fs/binfmt_flat.c:479: error: implicit declaration of function 'flat_old_ram_flag'
/home/bunk/linux/kernel-2.6/git/linux-2.6/fs/binfmt_flat.c:755: error: implicit declaration of function 'flat_set_persistent'
/home/bunk/linux/kernel-2.6/git/linux-2.6/fs/binfmt_flat.c:757: error: implicit declaration of function 'flat_get_relocate_addr'
/home/bunk/linux/kernel-2.6/git/linux-2.6/fs/binfmt_flat.c:765: error: implicit declaration of function 'flat_get_addr_from_rp'
/home/bunk/linux/kernel-2.6/git/linux-2.6/fs/binfmt_flat.c:781: error: implicit declaration of function 'flat_put_addr_at_rp'

Reported-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Tested-by: David Howells <dhowells@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>