bpf, docs: Add myself to BPF docs MAINTAINERS entry

In commit 7e2a9eb ("docs, bpf: Ensure IETF's BPF mailing list gets
copied for ISA doc changes"), a new MAINTAINERS entry was added for any
BPF IETF documentation updates for the ongoing standardization process.
I've been making it a point to try and review as many BPF documentation
patches as possible, and have made a committment to Alexei to
consistently review BPF standardization patches going forward. This
patch adds my name as a reviewer to the MAINTAINERS entry for the
standardization effort.

Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230214223553.78353-1-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

MAINTAINERS

@@ -4024,6 +4024,7 @@ S:	Maintained
 F:	tools/testing/selftests/bpf/
 
 BPF [DOCUMENTATION] (Related to Standardization)
+R:	David Vernet <void@manifault.com>
 L:	bpf@vger.kernel.org
 L:	bpf@ietf.org
 S:	Maintained