ftrace: Add support to resolve module symbols in ftrace_lookup_symbols

ftrace: Add support to resolve module symbols in ftrace_lookup_symbols

Currently ftrace_lookup_symbols iterates only over core symbols,
adding module_kallsyms_on_each_symbol call to check on modules
symbols as well.

Also removing 'args.found == args.cnt' condition, because it's
already checked in kallsyms_callback function.

Also removing 'err < 0' check, because both *kallsyms_on_each_symbol
functions do not return error.

Reported-by: Martynas Pumputis <m@lambda.lt>
Acked-by: Song Liu <song@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20221025134148.3300700-3-jolsa@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>