net-dns/pdns-recursor: Version bump to v3.5.3

No changes to the EBuild.

Changes since 3.5.2:

 * 3.5 replaced our ANY query with A+AAAA for users with IPv6 enabled.
   Extensive measurements by Darren Gamble showed that this change had a
   non-trivial performance impact. We now do the ANY query like before,
   but fall back to the individual A+AAAA queries when necessary. Change
   in commit 1147a8b.

 * The IPv6 address for d.root-servers.net was added in commit 66cf384,
   thanks Ralf van der Enden.

 * We now drop packets with a non-zero opcode (i.e. special packets like
   DNS UPDATE) earlier on. If the experimental pdns-distributes-queries
   flag is enabled, this fix avoids a crash. Normal setups were never
   susceptible to this crash. Code in commit 35bc40d, closes ticket 945.

 * TXT handling was somewhat improved in commit 4b57460, closing
   ticket 795.

http://doc.powerdns.com/html/changelog.html#changelog-recursor-3.5.3
net-dns/pdns-recursor: RepoMan satisfied.