[PATCH] ppc32: Don't sleep in flush_dcache_icache_page()

flush_dcache_icache_page() will be called on an instruction page fault.  We
can't sleep in the fault handler, so use kmap_atomic() instead of just
kmap() for the Book-E case.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
Acked-by: Matt Porter <mporter@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>