K 10
svn:author
V 6
kevans
K 8
svn:date
V 27
2018-06-20T03:31:19.795893Z
K 7
svn:log
V 439
sort(1): Fix -m when only implicit stdin is used for input

Observe:

printf "a\nb\nc\n" > /tmp/foo
# Next command results in no output
cat /tmp/foo | sort -m
# Next command results in proper output
cat /tmp/foo | sort -m -
# Also works:
sort -m /tmp/foo

Some const'ification was done to simplify the actual solution of adding "-"
explicitly to the file list if we didn't have any file arguments left over.

PR:		190099
MFC after:	1 week

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