mlxsw: core_thermal: Simplify rollback

During rollback, instead of calling mlxsw_thermal_module_fini() for all
the modules, only call it for modules that were successfully
initialized. This is not a bug fix since mlxsw_thermal_module_fini()
first checks that the module was initialized.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Vadim Pasternak <vadimp@nvidia.com>
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Wojciech Drewek <wojciech.drewek@intel.com>
Link: https://patch.msgid.link/905bebc45f6e246031f0c5c177bba8efe11e05f5.1722345311.git.petrm@nvidia.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>