git: hier.7: Use .Xr

[Sascha Wildner]

commit 6774184802ef406856bf1f220dce8eb12b21a0d1
Author: Sascha Wildner <***@online.de>
Date: Sun Dec 2 04:24:54 2018 +0100

hier.7: Use .Xr

Summary of changes:
share/man/man7/hier.7 | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

http://gitweb.dragonflybsd.org/dragonfly.git/commitdiff/6774184802ef406856bf1f220dce8eb12b21a0d1