powerpc: move math-emu over to arch/powerpc

Towards the goal of having arch/powerpc not build anything over in arch/ppc
move math-emu over.  Also, killed some references to arch/ppc/ in the
arch/powerpc Makefile which should belong in drivers/ when the particular
sub-arch's move over to arch/powerpc.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
diff --git a/arch/ppc/Makefile b/arch/ppc/Makefile
index cde5fa8..87bd063 100644
--- a/arch/ppc/Makefile
+++ b/arch/ppc/Makefile
@@ -69,7 +69,7 @@
 core-$(CONFIG_4xx)		+= arch/ppc/platforms/4xx/
 core-$(CONFIG_83xx)		+= arch/ppc/platforms/83xx/
 core-$(CONFIG_85xx)		+= arch/ppc/platforms/85xx/
-core-$(CONFIG_MATH_EMULATION)	+= arch/ppc/math-emu/
+core-$(CONFIG_MATH_EMULATION)	+= arch/powerpc/math-emu/
 core-$(CONFIG_XMON)		+= arch/ppc/xmon/
 core-$(CONFIG_APUS)		+= arch/ppc/amiga/
 drivers-$(CONFIG_8xx)		+= arch/ppc/8xx_io/