Summary: Handle R_X86_64_64 the same way as R_X86_64_32; `getSizeForType` takes care of the size: ```x86_64 ABI relocation types Name Value Field Calculation R_X86_64_64 1 word64 S + A R_X86_64_32 10 word32 S + A ``` (cherry picked from FBD29370417)