gdb.ada/info_exc.exp,mi_exc_info.exp: handle runtimes with full debug info.

gdb.ada/info_exc.exp,mi_exc_info.exp: handle runtimes with full debug info.

If the runtime has full debug info, then the non-standard exceptions
declared in the GNAT runtime will appear in the list of exceptions
printed by GDB ("info exceptions" or "-info-ada-exceptions").
This is valid output, so this patch allows for it.

gdb/testsuite/ChangeLog:

        * gdb.ada/info_exc.exp: Allow other global exceptions to be
        listed in the output of "info exceptions".
        * gdb.ada/mi_exc_info.exp: Allow other global exceptions to be
        listed in the output of "-info-ada-exceptions".