libbpf: Fix error handling bug in btf_dump__new

Fix missing jump to error handling in btf_dump__new, found by Coverity static
code analysis.

Fixes: 9f81654e ("libbpf: Expose BTF-to-C type declaration emitting API")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200117060801.1311525-2-andriin@fb.com

tools/lib/bpf/btf_dump.c

@@ -142,6 +142,7 @@ struct btf_dump *btf_dump__new(const struct btf *btf,
 	if (IS_ERR(d->type_names)) {
 		err = PTR_ERR(d->type_names);
 		d->type_names = NULL;
+		goto err;
 	}
 	d->ident_names = hashmap__new(str_hash_fn, str_equal_fn, NULL);
 	if (IS_ERR(d->ident_names)) {