Update maintainer list

[skip ci]

libs/maintainers.txt

@@ -44,7 +44,7 @@ detail                Beman Dawes <bdawes -at- acm.org>, Robert Ramey <ramey -at
 disjoint_sets         Jeremy Siek <jeremy.siek -at- gmail.com>
 dll                   Antony Polukhin <antoshkka -at- gmail.com>
 dynamic_bitset        Jeremy Siek <jeremy.siek -at- gmail.com>
-endian                Beman Dawes <bdawes -at- acm.org>
+endian                Peter Dimov <pdimov -at- pdimov.com>
 exception             Emil Dotchevski <emil -at- revergestudios.com>
 fiber                 Oliver Kowalke <oliver.kowalke -at- gmail.com>
 filesystem            Beman Dawes <bdawes -at- acm.org>, Andrey Semashev <andrey.semashev -at- gmail.com>