MFH: r419065

x11-fonts/fontconfig: don't touch user font cache on install

This matches USES=fonts (@fc, @fcfontsdir) behavior.

PR: 207263
Submitted by: Tatsuki Makino <tatsuki_makino@hotmail.com>
Approved by: maintainer timeout (5 months)
Approved by: ports-secteam (feld)