libbpf: Fix error path in bpf_object__elf_init()

stable inclusion
from stable-5.10.27
commit 86e525bc04f24d503cc6178d19f61b51727e6e91
bugzilla: 51493

--------------------------------

[ Upstream commit 8f3f5792 ]

When it failed to get section names, it should call into
bpf_object__elf_finish() like others.

Fixes: 88a82120 ("libbpf: Factor out common ELF operations and improve logging")
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210317145414.884817-1-namhyung@kernel.org


Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Chen Jun <chenjun102@huawei.com>
Acked-by:   Weilong Chen <chenweilong@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>