[PATCH][gdb, c++] Improve error message when using libstdcxx without SDT probes

[Tom Tromey]

>>>>> "Tom" == Tom de Vries <tdevries@suse.de> writes:

Tom> When using catch catch/rethrow/catch, a libstdcxx with SDT probes is required
Tom> for both the regexp argument, and the convenience variable $_exception (
Tom> https://sourceware.org/gdb/current/onlinedocs/gdb/Set-Catchpoints.html ).

Tom> +  if (pc_probe.prob == NULL)
Tom> +    error (_("did not find exception probe (does libstdcxx have SDT probes?)"));

I think it's more normal to start an error with a capital letter.
Also I'd suggest writing "libstdc++" here.

Ok with those changes.

thanks,
Tom