www-apps/grafana: fix pid file permission.

Due to a fact that the service is running as a user named grafana, the process
did not have permissions to create a file in /run. It could be mitigated by
changing permissions of /run or running service as privileged user or avoiding
systemd.  This patch moves pid file to subdirectory and adds RuntimeDirectory
entry to the definition of the service.

Closes: https://bugs.gentoo.org/628328

Package-Manager: Portage-2.3.19, Repoman-2.3.6
Closes: https://github.com/gentoo/gentoo/pull/8765

www-apps/grafana-bin/files/grafana.service

@@ -9,10 +9,11 @@ User=grafana
 Group=grafana
 Type=simple
 Restart=on-failure
+RuntimeDirectory=grafana
 WorkingDirectory=/usr/share/grafana
 ExecStart=/usr/bin/grafana-server                      \
     --config=/etc/grafana/grafana.ini                  \
-    --pidfile=/run/grafana.pid                         \
+    --pidfile=/run/grafana/grafana.pid                 \
     cfg:default.paths.logs=/var/log/grafana            \
     cfg:default.paths.data=/var/lib/grafana            \
     cfg:default.paths.plugins=/var/lib/grafana/plugins