sparc,sparc64: unify lib/

o Renamed files in sparc64 to <name>_64.S when identical
  to sparc32 files.
o iomap.c were equal for sparc32 and sparc64
o adjusted sparc/Makefile now we have only one lib/

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>