[POWERPC] 8xx: Move softemu8xx.c from arch/ppc

Previously, Soft_emulate_8xx was called with no implementation, resulting in
build failures whenever building 8xx without math emulation.  The
implementation is copied from arch/ppc to resolve this issue.

However, this sort of minimal emulation is not a very good idea other than
for compatibility with existing userspaces, as it's less efficient than
soft-float and can mislead users into believing they have soft-float.  Thus,
it is made a configurable option, off by default.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 6f5155d..3180457 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -198,6 +198,17 @@
 	  unit, which will allow programs that use floating-point
 	  instructions to run.
 
+config 8XX_MINIMAL_FPEMU
+	bool "Minimal math emulation for 8xx"
+	depends on 8xx && !MATH_EMULATION
+	help
+	  Older arch/ppc kernels still emulated a few floating point
+	  instructions such as load and store, even when full math
+	  emulation is disabled.  Say "Y" here if you want to preserve
+	  this behavior.
+
+	  It is recommended that you build a soft-float userspace instead.
+
 config IOMMU_VMERGE
 	bool "Enable IOMMU virtual merging"
 	depends on PPC64