examples/power: fix core id with JSON commands

examples/power: fix core id with JSON commands

This patch fixes a bug introduced in the 64-core limitation
enhancement where the core_id is inadvertently converted from
virtual to physical even though it may already be a physical
core_id.

We should be using the core_type field, and only converting via
hypervisor when core_type is set to CORE_TYPE_VIRTUAL

Fixes: 5776b7a371d1 ("examples/power: allow VM to use lcores over 63")

Signed-off-by: David Hunt <david.hunt@intel.com>
Reviewed-by: Lei Yao <lei.a.yao@intel.com>
Tested-by: Lei Yao <lei.a.yao@intel.com>