ssl: improve table checks ssl_pem_cache_SUITE
ssl: improve table checks ssl_pem_cache_SUITE

- variable renames
- adjust test certificate chain building
- adjust verification instructions

dumbbell/otp,g-andrade/otp,vinoski/otp,g-andrade/otp,dgud/otp,g-andrade/otp,mikpe/otp,potatosalad/otp,potatosalad/otp,erlang/otp,g-andrade/otp,erlang/otp,isvilen/otp,emacsmirror/erlang,erlang/otp,erlang/otp,dumbbell/otp,vinoski/otp,mikpe/otp,mikpe/otp,vinoski/otp,vinoski/otp,isvilen/otp,potatosalad/otp,dgud/otp,dumbbell/otp,bjorng/otp,isvilen/otp,mikpe/otp,mikpe/otp,dumbbell/otp,dgud/otp,dgud/otp,dumbbell/otp,isvilen/otp,vinoski/otp,isvilen/otp,erlang/otp,dumbbell/otp,emacsmirror/erlang,bjorng/otp,bjorng/otp,emacsmirror/erlang,g-andrade/otp,dgud/otp,mikpe/otp,dgud/otp,emacsmirror/erlang,isvilen/otp,potatosalad/otp,potatosalad/otp,dumbbell/otp,dgud/otp,potatosalad/otp,dgud/otp,g-andrade/otp,isvilen/otp,mikpe/otp,vinoski/otp,bjorng/otp,g-andrade/otp,erlang/otp,vinoski/otp,emacsmirror/erlang,isvilen/otp,bjorng/otp,dumbbell/otp,mikpe/otp,vinoski/otp,erlang/otp,potatosalad/otp,vinoski/otp,bjorng/otp,erlang/otp,potatosalad/otp,erlang/otp,dumbbell/otp,bjorng/otp,dumbbell/otp,dgud/otp,emacsmirror/erlang,isvilen/otp,dgud/otp,potatosalad/otp,emacsmirror/erlang,emacsmirror/erlang,emacsmirror/erlang,vinoski/otp,emacsmirror/erlang,g-andrade/otp,mikpe/otp,mikpe/otp,g-andrade/otp,bjorng/otp,bjorng/otp,potatosalad/otp,bjorng/otp,erlang/otp,isvilen/otp,g-andrade/otp