CAddrMan.GetAddr() would previously limit the number and percentage of
addresses returned (to ADDRMAN_GETADDR_MAX (1000) and
ADDRMAN_GETADDR_MAX_PCT (23) respectively). Instead, make it the callers
responsibility to specify the maximum addresses and percentage they want
returned.
For net_processing, the maximums are MAX_ADDR_TO_SEND (1000) and
MAX_PCT_ADDR_TO_SEND (23). For rpc/net, the maximum is specified by the
client.
This is a backport of core#19658 [1/3]
https://github.com/bitcoin/bitcoin/pull/19658/commits/f26502e9fc8a669b30717525597e3f468eaecf79