target/arm: Replace magic GIC values by proper definitions

Prefer the FIELD_DP64() macro and self-describing GIC
definitions over magic values.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
1 file changed