FRV: permit the memory to be located elsewhere in NOMMU mode

Permit the memory to be located somewhere other than address 0xC0000000 in
NOMMU mode.  The configuration options are already present, it just
requires wiring up in the linker script.

Note that only a limited set of locations of runtime addresses are available
because of the way the CPU protection registers work.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>