Auto merge of #1612 - GrayJack:fix_utmpx_debug_solarish, r=gnzlbg

Solarish: Fix utmx Debug impl and re-add support for extra traits

Fix a bug where the compilation failed cause `utmpx.host` is bigger than 32 so we cannot print it.

Due to a break of compilation (only with extra trait enabled) on a Tier 2 platform, I do think it would be better to do another release as soon as proven fixing compilation