hwmon: (coretemp) Fix oops on driver load

hwmon: (coretemp) Fix oops on driver load

This is for stable kernel branch 3.0 only. Previous and later versions
have different code paths and are not affected by this bug.

If the CPU microcode is too old, the coretemp driver won't work. But
instead of failing gracefully, it currently oops. Check for NULL
platform device data to avoid this.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Durgadoss R <durgadoss.r@intel.com>
Acked-by: Guenter Roeck <guenter.roeck@ericsson.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>