perf probe: Fix to get the DW_AT_decl_file and DW_AT_call_file as unsinged data

perf probe: Fix to get the DW_AT_decl_file and DW_AT_call_file as unsinged data

DWARF version 5 standard Sec 2.14 says that

  Any debugging information entry representing the declaration of an object,
  module, subprogram or type may have DW_AT_decl_file, DW_AT_decl_line and
  DW_AT_decl_column attributes, each of whose value is an unsigned integer
  constant.

So it should be an unsigned integer data. Also, even though the standard
doesn't clearly say the DW_AT_call_file is signed or unsigned, the
elfutils (eu-readelf) interprets it as unsigned integer data and it is
natural to handle it as unsigned integer data as same as DW_AT_decl_file.
This changes the DW_AT_call_file as unsigned integer data too.

Fixes: 3f4460a28fb2f73d ("perf probe: Filter out redundant inline-instances")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: stable@vger.kernel.org
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: https://lore.kernel.org/r/166761727445.480106.3738447577082071942.stgit@devnote3
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>