When checking a transfer for being expired via `Curl_timeleft_ms()`,
eleminate the `bool connecting` parameter and have the function check
the `mstate` of the transfer instead.
Advantages:
* eleminate the caller needing awareness if the transfer is
connecting or in a later state
* fix pingpong timeout handling to check the correct timeout
during "proto_connect" phases
* avoid using "connecting" timeouts during establishing a secondary
connection (e.g. FTP) since this would use the timestamp from
the original, primary connect and thus be wrong
Reported-by: Wyuer on github
Fixes#20347Closes#20354