Erm... why did you have a drill anywhere near to start with? Bigger rims don't suddenly have larger bolt holes...
And yes you've compromised the design so there is now risk. Without knowing how big you've drilled them out its impossible to comment more, you may well have affected the seating area to detriment also (well you will have regardless but to what extent is impossible to know) but to be honest I'm struggling to not such say - wtf