[Object] Normalize BBAddrMap decode address types in ELF (#187962)
This is part of patches to port BBAddrMap to COFF.
DataExtractor::getAddress reads 4 or 8 bytes according to AddressSize and
returns a uint64_t container value. This code path already sets AddressSize
from ELFT::Is64Bits and stores range/function addresses as uint64_t.
Replace temporary uintX_t/unsigned values in this decoder path with uint64_t
and remove the redundant cast from getAddress(). This preserves behavior for
ELF32/ELF64 inputs.
This is a preparatory step for extracting a format-agnostic BBAddrMap decoder.
