bpf: One more maintainer for libbpf and BPF selftests

I've been working on BPF verifier, BPF selftests and, to some extent,
libbpf, for some time. As suggested by Andrii and Alexei,
I humbly ask to add me to maintainers list:
- As reviewer   for BPF [GENERAL]
- As maintainer for BPF [LIBRARY]
- As maintainer for BPF [SELFTESTS]

This patch adds dedicated entries to MAINTAINERS.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20240126032554.9697-1-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

MAINTAINERS

@@ -3792,6 +3792,7 @@ M:	Alexei Starovoitov <ast@kernel.org>
 M:	Daniel Borkmann <daniel@iogearbox.net>
 M:	Andrii Nakryiko <andrii@kernel.org>
 R:	Martin KaFai Lau <martin.lau@linux.dev>
+R:	Eduard Zingerman <eddyz87@gmail.com>
 R:	Song Liu <song@kernel.org>
 R:	Yonghong Song <yonghong.song@linux.dev>
 R:	John Fastabend <john.fastabend@gmail.com>
@@ -3852,6 +3853,7 @@ F:	net/unix/unix_bpf.c
 
 BPF [LIBRARY] (libbpf)
 M:	Andrii Nakryiko <andrii@kernel.org>
+M:	Eduard Zingerman <eddyz87@gmail.com>
 L:	bpf@vger.kernel.org
 S:	Maintained
 F:	tools/lib/bpf/
@@ -3909,6 +3911,7 @@ F:	security/bpf/
 
 BPF [SELFTESTS] (Test Runners & Infrastructure)
 M:	Andrii Nakryiko <andrii@kernel.org>
+M:	Eduard Zingerman <eddyz87@gmail.com>
 R:	Mykola Lysenko <mykolal@fb.com>
 L:	bpf@vger.kernel.org
 S:	Maintained