gprofng: 31169 Source code locations can not be found in a C++ application

gprofng: 31169 Source code locations can not be found in a C++ application

gprofng incorrectly reads the form of the DW_FORM_ref_addr attribute for DWARF
Version 3 or later.
From DWARF specification:
  References that use the attribute form DW_FORM_ref_addr are specified to
  be four bytes in the DWARF 32-bit format and eight bytes in the DWARF
  64-bit format, while DWARF Version 2 specifies that such references have
  the same size as an address on the target system.

2023-12-18  Vladimir Mezentsev  <vladimir.mezentsev@oracle.com>

	PR gprofng/31169
	* src/DwarfLib.cc: Fix the reader for DW_FORM_ref_addr.