[BOLT][DWARF] Fix how DW_AT_high_pc [DW_FORM_udata] is handled

We were not handling correctly conversion from DW_AT_high_pc into DW_AT_ranges,
when size of DW_AT_high_pc is not 4/8 bytes.

Reviewed By: maksfb

Differential Revision: https://reviews.llvm.org/D120528