cpufreq: rename index as driver_data in cpufreq_frequency_table

The "index" field of struct cpufreq_frequency_table was never an
index and isn't used at all by the cpufreq core.  It only is useful
for cpufreq drivers for their internal purposes.

Many people nowadays blindly set it in ascending order with the
assumption that the core will use it, which is a mistake.

Rename it to "driver_data" as that's what its purpose is. All of its
users are updated accordingly.

[rjw: Changelog]
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/drivers/cpufreq/speedstep-centrino.c b/drivers/cpufreq/speedstep-centrino.c
index 618e6f4..0915e71 100644
--- a/drivers/cpufreq/speedstep-centrino.c
+++ b/drivers/cpufreq/speedstep-centrino.c
@@ -79,11 +79,11 @@
 
 /* Computes the correct form for IA32_PERF_CTL MSR for a particular
    frequency/voltage operating point; frequency in MHz, volts in mV.
-   This is stored as "index" in the structure. */
+   This is stored as "driver_data" in the structure. */
 #define OP(mhz, mv)							\
 	{								\
 		.frequency = (mhz) * 1000,				\
-		.index = (((mhz)/100) << 8) | ((mv - 700) / 16)		\
+		.driver_data = (((mhz)/100) << 8) | ((mv - 700) / 16)		\
 	}
 
 /*
@@ -307,7 +307,7 @@
 		per_cpu(centrino_model, cpu)->op_points[i].frequency
 							!= CPUFREQ_TABLE_END;
 	     i++) {
-		if (msr == per_cpu(centrino_model, cpu)->op_points[i].index)
+		if (msr == per_cpu(centrino_model, cpu)->op_points[i].driver_data)
 			return per_cpu(centrino_model, cpu)->
 							op_points[i].frequency;
 	}
@@ -501,7 +501,7 @@
 			break;
 		}
 
-		msr = per_cpu(centrino_model, cpu)->op_points[newstate].index;
+		msr = per_cpu(centrino_model, cpu)->op_points[newstate].driver_data;
 
 		if (first_cpu) {
 			rdmsr_on_cpu(good_cpu, MSR_IA32_PERF_CTL, &oldmsr, &h);