bpf: Swap the order of checking prog_info and map_info

This patch swaps the checking order.  It now checks the map_info
first and then prog_info.  It is a prep work for adding
test to the newly added fields (the map_ids of prog_info field
in particular).

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@fb.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>