target/arm: Widen NeonGenNarrowEnvFn return to 64 bits

While these functions really do return a 32-bit value,
widening the return type means that we need do less
marshalling between TCG types.

Remove NeonGenNarrowEnvFn typedef; add NeonGenOne64OpEnvFn.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20240912024114.1097832-27-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
5 files changed