Move -msoft-float to ToolchainCflags

-msoft-float is equivalent to -mfloat-abi=soft, which means we need to
make sure the order is correct if we also specify -mfloat-abi=softfp.
Since the Neon support (with -mfloat-abi=softfp) is in the cpu-specific
ToolchainCflags, move the generic definition into ToolchainCflags as
well.

This wasn't actually causing problems when compiling, since the normal
toolchain.Cflags is before toolchain.ToolchainCflags, but the makevars
code accidentally reversed this. That will be fixed as well, but this
will protect against similar problems in the future.

Change-Id: If6f37c845210105f84769bab45fde5d7fdc2fe09
diff --git a/cc/arm_device.go b/cc/arm_device.go
index d583590..766eea6 100644
--- a/cc/arm_device.go
+++ b/cc/arm_device.go
@@ -24,12 +24,12 @@
 var (
 	armToolchainCflags = []string{
 		"-mthumb-interwork",
+		"-msoft-float",
 	}
 
 	armCflags = []string{
 		"-fno-exceptions", // from build/core/combo/select.mk
 		"-Wno-multichar",  // from build/core/combo/select.mk
-		"-msoft-float",
 		"-ffunction-sections",
 		"-fdata-sections",
 		"-funwind-tables",