Revert "maint(sys-apps/systemd): Replace reload patch with upstream version."

This patch was not functionally equivalent to the original, roll back to
the original until a corrected version is accepted upstream.

This reverts commit 685a68db717dfaafe26340fd25aefde642a553aa.
Merge pull request #582 from marineam/reload

Revert "maint(sys-apps/systemd): Replace reload patch with upstream version"