tinyformat: force USE_VARIADIC_TEMPLATES
tinyformat: force USE_VARIADIC_TEMPLATES

backports bitcoin@9eaa0afa6ec5d3dd01e4d01121314ef51f2bc305
Darknet-Crypto/Darknet,PIVX-Project/PIVX,Darknet-Crypto/Darknet,PIVX-Project/PIVX,Darknet-Crypto/Darknet,PIVX-Project/PIVX,Darknet-Crypto/Darknet,PIVX-Project/PIVX,PIVX-Project/PIVX,PIVX-Project/PIVX,PIVX-Project/PIVX,Darknet-Crypto/Darknet,PIVX-Project/PIVX,Darknet-Crypto/Darknet,PIVX-Project/PIVX