CPU: fix M2 family detection

[bayandin]

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On MacBook Air with M2 chip brew config return dunno family (while arm_blizzard_avalanche is expected):

$ brew config | grep CPU
CPU: octa-core 64-bit dunno

And here's the corresponding sysctl -A output:

% sysctl -A | grep hw.cpufamily
hw.cpufamily: -634136515

It looks like some signed int32 overflow happens somewhere for 0xda33d83d, which causes it to return a negative number.

These changes will also affect CPU family detection for ARMv8.2-A (Monsoon, Mistral) (https://en.wikipedia.org/wiki/Apple_A11) and for ARMv8.0-A (Twister) (https://en.wikipedia.org/wiki/Apple_A9 / https://en.wikipedia.org/wiki/Apple_A9X). They are used in iPhones only, so I don't think it will affect anything real.

[BrewTestBot]

Review period will end on 2022-11-16 at 11:27:05 UTC.

[BrewTestBot]

Review period ended.