Clean up quote_fname, quote_fname_ufs, and quote_dname

Moves definitions of the quote_xxx functions from ufs.c where they are not
used to dir.c where they are used.

Adds a parameter to each of the quote_xxx functions to supply the length
of the storage allocated for the result string, and change strcpy() to
strlcpy() to avoid potential memory smash if used carelessly.

Author: nbriggs

inc/ufsdefs.h

@@ -11,9 +11,6 @@ int unixpathname(char *src, char *dst, int dstlen, int versionp, int genp, char
 int unixpathname(char *src, char *dst, size_t dstlen, int versionp, int genp);
 #endif
 int lisppathname(char *fullname, char *lispname, size_t lispnamesize, int dirp, int versionp);
-int quote_fname(char *file);
-int quote_fname_ufs(char *file);
-int quote_dname(char *dir);
 #ifdef DOS
 init_host_filesystem(void);
 exit_host_filesystem(void);