target/arm: Implement VFP fp16 VMLA, VMLS, VNMLS, VNMLA, VNMUL

Implement fp16 versions of the VFP VMLA, VMLS, VNMLS, VNMLA, VNMUL
instructions. (These are all the remaining ones which we implement
via do_vfp_3op_[hsd]p().)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20200828183354.27913-5-peter.maydell@linaro.org

target/arm/vfp_helper.c

@@ -261,6 +261,11 @@ VFP_BINOP(minnum)
 VFP_BINOP(maxnum)
 #undef VFP_BINOP
 
+dh_ctype_f16 VFP_HELPER(neg, h)(dh_ctype_f16 a)
+{
+    return float16_chs(a);
+}
+
 float32 VFP_HELPER(neg, s)(float32 a)
 {
     return float32_chs(a);