system/system76-power: Mark 32bit as unsupported.
Fails to compile on 32-bit, and upstream does not support 32-bit:
https://github.com/pop-os/system76-power/issues/322
We have no expectation of users running a 32-bit OS, so we only care about 64-bit architectures.
Signed-off-by: Erich Ritz erich.public@protonmail.com