samples: bpf: rename struct bpf_map_def to avoid conflict with libbpf

Both tools/lib/bpf/libbpf.h and samples/bpf/bpf_load.h define their
own version of struct bpf_map_def.  The version in bpf_load.h has
more fields.  libbpf does not support inner maps and its definition
of struct bpf_map_def lacks the related fields.  Rename the definition
in bpf_load.h (samples/bpf) to avoid conflicts.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

samples/bpf/bpf_load.h

@@ -7,7 +7,7 @@
 #define MAX_MAPS 32
 #define MAX_PROGS 32
 
-struct bpf_map_def {
+struct bpf_load_map_def {
 	unsigned int type;
 	unsigned int key_size;
 	unsigned int value_size;
@@ -21,7 +21,7 @@ struct bpf_map_data {
 	int fd;
 	char *name;
 	size_t elf_offset;
-	struct bpf_map_def def;
+	struct bpf_load_map_def def;
 };
 
 typedef void (*fixup_map_cb)(struct bpf_map_data *map, int idx);