perf tools: Normalize sq_quote_argv() error reporting

It already returns whatever strbuf_(grow|addch)() returns in case of
failure, so just return -ENOSPC in the only case where it was die()ing.
When it returns, its only caller will call die() anyway, so no need to
be so eager, die later.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-as05b7mbogprlwi8iarwns8e@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/quote.c

@@ -54,7 +54,7 @@ int sq_quote_argv(struct strbuf *dst, const char** argv, size_t maxlen)
 			break;
 		ret = sq_quote_buf(dst, argv[i]);
 		if (maxlen && dst->len > maxlen)
-			die("Too many or long arguments");
+			return -ENOSPC;
 	}
 	return ret;
 }