Add missing backslash escapes to suite file.

Add missing backslash escapes to suite file.

Hyphens in command line options should be backslash-escaped to prevent
man(1) from outputting a non-ascii hyphen character in utf8 mode as
this thwarts copy+paste and searching.

Distributions generally put

	.if '\*[.T]'utf8' \{\
	.  char ' \[aq]
	.  char - \-
	.  char ^ \[ha]
	.  char ` \[ga]
	.  char ~ \[ti]
	.\}

in /usr/lib/groff/site-tmac/man.local to deal with this brain damage,
but it does not hurt to properly escape the option dashes in the roff
sections of the man file. We can't do that in the other parts of the
suite file, however, as these backslashes would also show up in the
--detailed-help output.

See the PROBLEMS file in the groff source code and

	https://lwn.net/Articles/947941/

for details.