target-arm: Rename A32 VFP conversion helpers

The VFP conversion helpers for A32 round to zero as this is the only
rounding mode supported. Rename these helpers to make it clear that
they round to zero and are not suitable for use in the AArch64 code.

Signed-off-by: Will Newton <will.newton@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
diff --git a/target-arm/helper.h b/target-arm/helper.h
index dd1160e..b785623 100644
--- a/target-arm/helper.h
+++ b/target-arm/helper.h
@@ -115,14 +115,14 @@
 DEF_HELPER_2(vfp_tosizs, i32, f32, ptr)
 DEF_HELPER_2(vfp_tosizd, i32, f64, ptr)
 
-DEF_HELPER_3(vfp_toshs, i32, f32, i32, ptr)
-DEF_HELPER_3(vfp_tosls, i32, f32, i32, ptr)
-DEF_HELPER_3(vfp_touhs, i32, f32, i32, ptr)
-DEF_HELPER_3(vfp_touls, i32, f32, i32, ptr)
-DEF_HELPER_3(vfp_toshd, i64, f64, i32, ptr)
-DEF_HELPER_3(vfp_tosld, i64, f64, i32, ptr)
-DEF_HELPER_3(vfp_touhd, i64, f64, i32, ptr)
-DEF_HELPER_3(vfp_tould, i64, f64, i32, ptr)
+DEF_HELPER_3(vfp_toshs_round_to_zero, i32, f32, i32, ptr)
+DEF_HELPER_3(vfp_tosls_round_to_zero, i32, f32, i32, ptr)
+DEF_HELPER_3(vfp_touhs_round_to_zero, i32, f32, i32, ptr)
+DEF_HELPER_3(vfp_touls_round_to_zero, i32, f32, i32, ptr)
+DEF_HELPER_3(vfp_toshd_round_to_zero, i64, f64, i32, ptr)
+DEF_HELPER_3(vfp_tosld_round_to_zero, i64, f64, i32, ptr)
+DEF_HELPER_3(vfp_touhd_round_to_zero, i64, f64, i32, ptr)
+DEF_HELPER_3(vfp_tould_round_to_zero, i64, f64, i32, ptr)
 DEF_HELPER_3(vfp_shtos, f32, i32, i32, ptr)
 DEF_HELPER_3(vfp_sltos, f32, i32, i32, ptr)
 DEF_HELPER_3(vfp_uhtos, f32, i32, i32, ptr)