perf probe-event: Better error message for a too-long probe name

This is a common failure mode when probing userspace C++ code (where the
mangling adds significant length to the symbol names).

Prior to this patch, only a very generic error message is produced,
making the user guess at what the issue is.

Signed-off-by: Dima Kogan <dima@secretsauce.net>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lore.kernel.org/r/20240416045533.162692-3-dima@secretsauce.net


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>