[Info-vax] Building latest C-Kermit under OpenVMS gives errors

[Steven Schweda]

> I've been in touch with Frank da Cruz and supplied the macOS patches.
> [...]

   Did you try it with my (not-entirely-VMS-specific) changes for
9.0.305 Alpha.04?  There are multiple ways to eliminate the MAXPATHLEN
problems, but I prefer my scheme, which largely eliminates MAXPATHLEN.

   Around here, the Mac compiler has a whole pile of warnings.  They
might be mostly unimportant, but the compiler-suggested changes should
be harmless everyplace.  And there are some things which look actually
bad, like, for example:

ckcuni.c:8272:11: warning: use of logical '&&' with constant operand
      [-Wconstant-logical-operand]
    if (c && 0xff80)                    /* 7 bits */
          ^  ~~~~~~
ckcuni.c:8272:11: note: use '&' for a bitwise operation
    if (c && 0xff80)                    /* 7 bits */
          ^~
          &
ckcuni.c:8272:11: note: remove constant to silence this warning
    if (c && 0xff80)                    /* 7 bits */
         ~^~~~~~~~~
1 warning generated.

   Someone ought to inspect these things, at least.