Fix hyphen in place of underscore.

Fix missing 'by_cipher' path component in the caveats section.

--- share/man/man7/mirroring-ports.7.dist	Thu Aug 27 10:29:16 2020
+++ share/man/man7/mirroring-ports.7	Fri May 16 12:16:46 2025
@@ -128,15 +128,15 @@
 depend on distfiles mirrors to carry what they need irrespective of those
 synchronization issues.
 The
-.Pa ${DISTFILES}/by-cipher/sha256
+.Pa ${DISTFILES}/by_cipher/sha256
 directory provides more persistent access to the distfiles,
 indexed through the actual checksums that the files should match.
 Provided mirroring is run sufficiently often,
 two versions of the same distfile with respective checksums cksum1 and cksum2
 will be available under the names
-.Pa ${DISTFILES}/sha256/c1/cksum1/distfile
+.Pa ${DISTFILES}/by_cipher/sha256/c1/cksum1/distfile
 and
-.Pa ${DISTFILES}/sha256/c2/cksum2/distfile .
+.Pa ${DISTFILES}/by_cipher/sha256/c2/cksum2/distfile .
 .Pp
 If
 .Ev REFETCH