FogBugz #532583-3: mtd: a10sr: Add A10SR HWMON

commit  97b03841ca4101d65a08e9ebe2283f19c42a5de0 from
https://github.com/altera-opensource/linux-socfpga.git



Add HWMON to the A10 System Resource Multi-Function Device.
This fixes a previous patch
['commit b5678c1b894d ("FogBugz #411698-2: Add Altera A10-SR
                        power supply alarms")']
that removed this change when cherry-picked.

Signed-off-by: Thor Thayer <thor.thayer@linux.intel.com>
Signed-off-by: Meng Li <Meng.Li@windriver.com>