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>

arch/powerpc/math-emu/frsp.c

@@ -0,0 +1,25 @@
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <asm/uaccess.h>
+
+#include "soft-fp.h"
+#include "double.h"
+#include "single.h"
+
+int
+frsp(void *frD, void *frB)
+{
+	FP_DECL_D(B);
+
+#ifdef DEBUG
+	printk("%s: D %p, B %p\n", __FUNCTION__, frD, frB);
+#endif
+
+	__FP_UNPACK_D(B, frB);
+
+#ifdef DEBUG
+	printk("B: %ld %lu %lu %ld (%ld)\n", B_s, B_f1, B_f0, B_e, B_c);
+#endif
+
+	return __FP_PACK_DS(frD, B);
+}