nvmem: qfprom: Add Qualcomm QFPROM support.

This patch adds QFPROM support driver which is used by other drivers
like thermal sensor and cpufreq.

On MSM parts there are some efuses (called qfprom) these fuses store
things like calibration data, speed bins.. etc. Drivers like cpufreq,
thermal sensors would read out this data for configuring the driver.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>