cpufreq: kryo: Fix possible error code dereference

In event of error returned by the nvmem_cell_read() non-pointer value
may be dereferenced. Fix this with error handling.
Additionally free the allocated speedbin buffer, as per the API.

Fixes: 9ce36edd1a52 (cpufreq: Add Kryo CPU scaling driver)
Signed-off-by: NIlia Lin <ilia.lin@gmail.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/cpufreq/qcom-cpufreq-kryo.c

@@ -115,6 +115,8 @@ static int qcom_cpufreq_kryo_probe(struct platform_device *pdev)
 
 	speedbin = nvmem_cell_read(speedbin_nvmem, &len);
 	nvmem_cell_put(speedbin_nvmem);
+	if (IS_ERR(speedbin))
+		return PTR_ERR(speedbin);
 
 	switch (msm8996_version) {
 	case MSM8996_V3:
@@ -127,6 +129,7 @@ static int qcom_cpufreq_kryo_probe(struct platform_device *pdev)
 		BUG();
 		break;
 	}
+	kfree(speedbin);
 
 	for_each_possible_cpu(cpu) {
 		cpu_dev = get_cpu_device(cpu);