dns: synchronize resolve() docs and code

Synchronize the argument list for dns.resolve() with what's in the documentation.

Improve the error for a bad rrtype to be a TypeError rather than an Error.

Checklist

• make -j4 test (UNIX), or vcbuild test (Windows) passes
• tests and/or benchmarks are included
• commit message follows commit guidelines

Affected core subsystem(s)

dns