Auto merge of #30525 - semarie:ncpu, r=alexcrichton
Auto merge of #30525 - semarie:ncpu, r=alexcrichton

Should unbreak build (well, remove one reason to break) for *bsd target.

r? @alexcrichton

graydon/rust,aidancully/rust,GBGamer/rust,aidancully/rust,graydon/rust,aidancully/rust,aidancully/rust,graydon/rust,GBGamer/rust,graydon/rust,GBGamer/rust,GBGamer/rust,GBGamer/rust,GBGamer/rust,aidancully/rust,aidancully/rust,graydon/rust,GBGamer/rust,graydon/rust,GBGamer/rust