Changing an existing EC profile can have some nasty side effects
including crashing OSD's (which is why its guarded with a --force).

Update the ceph helper to log a warning and return if an EC profile
already exists, effectively making them immutable and avoiding
any related issues.

Reconfiguration of a pool would be undertaking using actions:

  - create new EC profile
  - create new pool using new EC profile
  - copy data from old pool to new pool
  - rename old pool
  - rename new pool to original pool name

this obviously requires an outage in the consuming application.

Change-Id: I630f6b6c5e3c6dd252a85cd373d7e204b9e77245
Closes-Bug: 1897517