hwmon: (coretemp) Merge pkgtemp with coretemp

This patch merges the pkgtemp with coretemp driver.
The sysfs interfaces for all cores in the same pkg
are shown under one directory, in hwmon. It also
supports CONFIG_HOTPLUG_CPU. So, the sysfs interfaces
are created when each core comes online and are
removed when it goes offline.

Signed-off-by: Durgadoss R <durgadoss.r@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
[guenter.roeck@ericsson.com: Fixed section reference errors]
Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>