perf srcline: Make sentinel reading for binutils addr2line more robust

The addr2line process is sent an address then multiple function,
filename:line "records" are read. To detect the end of output a ',' is
sent and for llvm-addr2line a ',' is then read back showing the end of
addrline's output.

For binutils addr2line the ',' translates to address 0 and we expect the
bogus filename marker "??:0" (see filename_split) to be sent from
addr2line.

For some kernels address 0 may have a mapping and so a seemingly valid
inline output is given and breaking the sentinel discovery:

  ```
  $ addr2line -e vmlinux -f -i
  ,
  __per_cpu_start
  ./arch/x86/kernel/cpu/common.c:1850
  ```

To avoid this problem enable the address dumping for addr2line (the -a
option). If an address of 0x0000000000000000 is read then this is the
sentinel value working around the problem above.

The filename_split still needs to check for "??:0" as bogus non-zero
addresses also need handling.

Reported-by: Changbin Du <[email protected]>
Signed-off-by: Ian Rogers <[email protected]>
Tested-by: Changbin Du <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Nathan Chancellor <[email protected]>
Cc: Nick Desaulniers <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Tom Rix <[email protected]>
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

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