coretemp support for Core i5 CPU

[Robert Hancock <hancockrwd@gmail.com>]

Trying to load the coretemp driver for CPU temperature monitoring on a 
Core i5 750 CPU gives:

coretemp: Unknown CPU model 1e
coretemp: Unknown CPU model 1e
coretemp: Unknown CPU model 1e
coretemp: Unknown CPU model 1e

Looks like this model needs to be added to the list in 
drivers/hwmon/coretemp.c. Though this doesn't really seem like a very 
good approach as we'll keep having to update this driver whenever a new 
CPU model gets released. Intel has a CPUID field that indicates if the 
thermal sensor is supported: "The processor supports a digital thermal 
sensor if CPUID.06H.EAX[0] = 1." We should likely be using this instead 
of hard-coded CPU model checks..