thermal/x86_pkg_temp: Sanitize package management

Packages are kept in a list, which must be searched over and over.

We can be smarter than that and just store the package pointers in an array
which is allocated at init time. Sizing of the array is determined from the
topology information. That makes the package search a simple array lookup.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>