libbpf: start v1.7 dev cycle

With libbpf 1.6.0 released, adjust libbpf.map and libbpf_version.h to
start v1.7 development cycles.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20250716175936.2343013-1-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Author: anakryiko

tools/lib/bpf/libbpf.map

@@ -446,3 +446,6 @@ LIBBPF_1.6.0 {
 		btf__add_decl_attr;
 		btf__add_type_attr;
 } LIBBPF_1.5.0;
+
+LIBBPF_1.7.0 {
+} LIBBPF_1.6.0;

tools/lib/bpf/libbpf_version.h

@@ -4,6 +4,6 @@
 #define __LIBBPF_VERSION_H
 
 #define LIBBPF_MAJOR_VERSION 1
-#define LIBBPF_MINOR_VERSION 6
+#define LIBBPF_MINOR_VERSION 7
 
 #endif /* __LIBBPF_VERSION_H */