httpClientSessionInit does not return rc/rsn to callers

[Gautham-coder]

httpClientSessionInit has its own set of status values it returns, but the actual rc/rsn of commands it does within are hidden behind compile-time printf statements.

This is unhelpful because this function does fail sometimes, and on zOS the reason is opaque and requires a GSK trace to then discover the cause. It just costs extra debug time then.

Is there any opposition to just add more arguments to httpClientSessionInit to allow passing back rc/rsn?