cmd/utils: renames flags related to http-rpc server (#20935)

* rpc flags related to starting http server renamed to http

* old rpc flags aliased and still functional

* pprof flags fixed

* renames gpo related flags

* linted

* renamed rpc flags for consistency and clarity

* added warn logs

* added more warn logs for all deprecated flags for consistency

* moves legacy flags to separate file, hides older flags under show-deprecated-flags command

* legacy prefix and moved some more legacy flags to legacy file

* fixed circular import

* added docs

* fixed imports lint error

* added notes about when flags were deprecated

* cmd/utils: group flags by deprecation date + reorder by date,

* modified deprecated comments for consistency, added warn log for --rpc

* making sure deprecated flags are still functional

* show-deprecated-flags command cleaned up

* fixed lint errors

* corrected merge conflict

* IsSet --> GlobalIsSet

* uncategorized flags, if not deprecated, displayed under misc

Co-authored-by: Martin Holst Swende <martin@swende.se>
# Conflicts:
#	cmd/geth/main.go
#	cmd/geth/usage.go
#	internal/debug/flags.go