The quickest way is to drill the heads off the bolts mounting the hugger. You can then remove the caliper mounting bolts, replace the pads and ride the bike leaving the hugger off for the time being.
To refit the hugger you have 3 options i) The easy method is to order some new caliper and hugger mounting bolts from the hugger manufacturer and when refitting them make sure there's plenty of copperslip on the hugger mounting bolts ii) Remove the caliper bolts at a later date drill out the seized bolts, re tap the holes and source some new bolts. iii) As per option ii but drill the hugger mounting bolts leaving some material left on the offending bolt then use a stud extractor to remove.
Personally, as the hugger mounting bolts are quire small, I'd go for option i and if you haven't got a stud extractor would probably be the cheapest especially if you lay it on with the hugger manufacturer about the fact that their fasteners have seized causing you all this grief you may get some foc replacements.
HTH
Dave