samples: bpf: include bpf/bpf.h instead of local libbpf.h

There are two files in the tree called libbpf.h which is becoming
problematic.  Most samples don't actually need the local libbpf.h
they simply include it to get to bpf/bpf.h.  Include bpf/bpf.h
directly instead.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
diff --git a/samples/bpf/bpf_load.h b/samples/bpf/bpf_load.h
index f9da59b..814894a 100644
--- a/samples/bpf/bpf_load.h
+++ b/samples/bpf/bpf_load.h
@@ -2,7 +2,7 @@
 #ifndef __BPF_LOAD_H
 #define __BPF_LOAD_H
 
-#include "libbpf.h"
+#include <bpf/bpf.h>
 
 #define MAX_MAPS 32
 #define MAX_PROGS 32