Merge commit 'acb089b983171667467adc66f56a723b609ed22e' into kbsd/vis
Highlights:
- Some style fixes
- Bumped mbbuf in istrsenvisx() to MB_LEN_MAX to avoid VLAs
- mbslength cannot go negative, so make it unsigned
- Further bounds checking & fix an additional overrun, with dlen == 0
- Avoid duplicate call to wcslen(start)