troff: fix mangled fonts and character files

All of these files appear to have been imported from sources in a
case-insensitive manner and consequently lost their original content.

- Hx, Hb, and Hi fonts should be narrow versions of Helvetica

- c[1-3] fonts should be condensed versions of Century Old Style

- the lH character should be a filled left hand symbol

- the rh character should be a stroked right hand symbol

- the rc character should be the right ceiling symbol

I've verified that these are the only files that collide with others
when ignoring case (aside from rc/bin/[Kk]ill but those are correct).

sys/lib/postscript/troff/Hx

@@ -1 +1 @@
-0x0000 0x00ff Helvetica-BoldOblique
+0x0000 0x00ff Helvetica-Narrow-BoldOblique