p2p: remove old debug commands #6275
As described in this issue: #6271, the code has strayed enough since ALLOW_DEBUG_COMMANDS was defaulted on, that turning it off no longer builds.
There are a couple ways to handle the issue, the least invasive being just fixing the build. But @moneromooo-monero commented that removing them altogether might be the better option, since they are effectively unusable.
This patch removes those debug commands and the associated code. If the consensus after further thought decides that it's too heavy-handed, I have another patch ready which simply gets things into a sane state that can build if someone decides to comment out the macro.