mpc52xx_psc_spi: remove code associated with !CONFIG_PPC_MERGE

Now that arch/ppc is gone we don't need CONFIG_PPC_MERGE anymore
remove the dead code associated with !CONFIG_PPC_MERGE.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: David Brownell <david-b@pacbell.net>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>