[patch] PR debug/61013: Change -g so that it will override -g1 but not -g3

[Cary Coutant]

>>         PR debug/61013
>>       * opts.c (common_handle_option): Don't special-case "-g".
>>       (set_debug_level): Default to at least level 2 with "-g".
>
> Ok.  Thanks,

Forgot to ask -- OK to backport to the 4.9 branch?

-cary