install: fix --external-ca-profile option
Commit dd47cfc75a69618f486abefb70f2649ebf8264e7 removed the ability
to set pki_req_ext_oid and pki_req_ext_data in the pkispawn config.
This results in the --external-ca-profile option never setting the
requested values in the CSR (the default V1 template type specifying
"SubCA" is always used).
Remove relevant fields from both ipaca_default.ini and
ipaca_customize.ini. This allows the IPA framework to set the
values (i.e. when --external-ca-type=ms-cs and
--external-ca-profile=... demand it). It also allows users to
override the pki_req_ext_* settings.
Part of: https://pagure.io/freeipa/issue/7548
Related: https://pagure.io/freeipa/issue/5608
Reviewed-By: Florence Blanc-Renaud <flo@redhat.com>