rgw: add support to consume user given ca cert for vault

rgw: add support to consume user given ca cert for vault

Currently RGW can authenticate with vault via SSL using system certs.
With this patch user can provide custom ca cert and location of the file
can be specified in ceph.conf like this :
	rgw_crypt_require_ssl = <file path>

Fixes: https://tracker.ceph.com/issues/47776
Signed-off-by: Jiffin Tony Thottan <jthottan@redhat.com>
(cherry picked from commit 424dca0f3866c62e5c51cc8b2a080d680fddbe7f)
Signed-off-by: Jiffin Tony Thottan <jthottan@redhat.com>
Conflicts:
	src/common/options/rgw.yaml.in
- added required changes in options.cc and legacy_config_opts.h