Fix use of a feature deprecated in OpenSSL 1.1
Fix use of a feature deprecated in OpenSSL 1.1

If OpenSSL 1.1 is configured in such a way that features deprecated in 1.1.0 are not built, then compile errors would result here.

DarthGandalf/znc,znc/znc,dgw/znc,Zarthus/znc,KiNgMaR/znc,kashike/znc,kashike/znc,dgw/znc,elyscape/znc,kashike/znc,Zarthus/znc,znc/znc,jreese/znc,kashike/znc,GLolol/znc,GLolol/znc,GLolol/znc,psychon/znc,KiNgMaR/znc,evilnet/znc,GLolol/znc,psychon/znc,jreese/znc,psychon/znc,evilnet/znc,DarthGandalf/znc,dgw/znc,jreese/znc,znc/znc,DarthGandalf/znc,BtbN/znc,KiNgMaR/znc,dgw/znc,markusj/znc,BtbN/znc,jreese/znc,evilnet/znc,kashike/znc,markusj/znc,KiNgMaR/znc,Phansa/znc,Phansa/znc,Phansa/znc,markusj/znc,evilnet/znc,Zarthus/znc,elyscape/znc,evilnet/znc,BtbN/znc,Phansa/znc,jreese/znc,Phansa/znc,psychon/znc,BtbN/znc,znc/znc,kashike/znc,elyscape/znc,elyscape/znc,Zarthus/znc,dgw/znc,KiNgMaR/znc,znc/znc,markusj/znc,DarthGandalf/znc,evilnet/znc,znc/znc,GLolol/znc,DarthGandalf/znc,DarthGandalf/znc,BtbN/znc,dgw/znc,elyscape/znc,jreese/znc,markusj/znc,Phansa/znc,markusj/znc,psychon/znc,GLolol/znc,psychon/znc,BtbN/znc,Zarthus/znc,elyscape/znc,KiNgMaR/znc,Zarthus/znc