BUG/MINOR: ssl/cli: fix "show ssl ca-file/crl-file" not to mix cli+ssl contexts

BUG/MINOR: ssl/cli: fix "show ssl ca-file/crl-file" not to mix cli+ssl contexts

The "show ca-file" and "show crl-file" commands mix some generic pointers
from the "ctx.cli" struct and context-specific ones from "ctx.ssl" while
both are in a union. It's fortunate that the p0 pointer in use is located
immediately before the first one used (it overlaps with next_ckchi_link,
and old_cafile_entry is safe). But should these fields be reordered or
slightly updated this will break.

Comments were added on top of the affected functions to indicate what they
use.

This needs to be backported to 2.5.