bpf, doc: add maintainers entry to related files

Add a MAINTAINERS entry to the skmsg and related files such that
patches, features, bug reports land with the right Cc.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

MAINTAINERS

@@ -8188,6 +8188,16 @@ S:	Maintained
 F:	net/l3mdev
 F:	include/net/l3mdev.h
 
+L7 BPF FRAMEWORK
+M:	John Fastabend <john.fastabend@gmail.com>
+M:	Daniel Borkmann <daniel@iogearbox.net>
+L:	netdev@vger.kernel.org
+S:	Maintained
+F:	include/linux/skmsg.h
+F:	net/core/skmsg.c
+F:	net/core/sock_map.c
+F:	net/ipv4/tcp_bpf.c
+
 LANTIQ / INTEL Ethernet drivers
 M:	Hauke Mehrtens <hauke@hauke-m.de>
 L:	netdev@vger.kernel.org