Fix non-default location of znc.pem when upgrading configs from pre-1.7.
Fix non-default location of znc.pem when upgrading configs from pre-1.7.

New options SSLDHParamFile and SSLKeyFile were pointing at the default
location instead of the same as SSLCertFile.

Thanks to @xelra for the report.

markusj/znc,dgw/znc,DarthGandalf/znc,Zarthus/znc,DarthGandalf/znc,znc/znc,BtbN/znc,elyscape/znc,dgw/znc,Zarthus/znc,znc/znc,Zarthus/znc,BtbN/znc,elyscape/znc,Zarthus/znc,znc/znc,psychon/znc,DarthGandalf/znc,dgw/znc,DarthGandalf/znc,elyscape/znc,markusj/znc,znc/znc,markusj/znc,markusj/znc,elyscape/znc,psychon/znc,BtbN/znc,znc/znc,BtbN/znc,markusj/znc,dgw/znc,DarthGandalf/znc,Zarthus/znc,dgw/znc,markusj/znc,psychon/znc,dgw/znc,elyscape/znc,BtbN/znc,psychon/znc,elyscape/znc,Zarthus/znc,psychon/znc,psychon/znc,BtbN/znc,znc/znc,DarthGandalf/znc