man: don't use non-breaking minuses when they're not necessary

man: don't use non-breaking minuses when they're not necessary

Technically you only need to escape a dash in troff when you
1. Want it to be a typographical minus
2. Need to prevent the typesetter potentially doing a line break at it
   (e.g. to prevent a -option being split apart)

so convert lots of "\-" to just "-" .

Signed-off-by: Sitsofe Wheeler <sitsofe@yahoo.com>