target/alpha, hppa: Remove unused parent_reset fields

target/alpha, hppa: Remove unused parent_reset fields

The Alpha and HPPA CPU class structs include a 'parent_reset'
field which is never used; delete them.

(These targets don't seem to implement reset at all; if they did they
should do it using the three-phase reset mechanism, which uses a
'ResettablePhases parent_phases' field instead of the old
'DeviceReset parent_reset' field.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20240830145812.1967042-6-peter.maydell@linaro.org