cpufreq: sti-cpufreq: Fix some formatting and misspelling issues

Kerneldoc format for attribute descriptions should be '@.*: '.

Fixes the following W=1 kernel build warning(s):

 drivers/cpufreq/sti-cpufreq.c:49: warning: cannot understand function prototype: 'struct sti_cpufreq_ddata '
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Cc: Patrice Chotard <patrice.chotard@st.com>
Cc: Pal Singh <ajitpal.singh@st.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

drivers/cpufreq/sti-cpufreq.c

@@ -40,11 +40,11 @@ enum {
 };
 
 /**
- * ST CPUFreq Driver Data
+ * struct sti_cpufreq_ddata - ST CPUFreq Driver Data
  *
- * @cpu_node		CPU's OF node
- * @syscfg_eng		Engineering Syscon register map
- * @regmap		Syscon register map
+ * @cpu:		CPU's OF node
+ * @syscfg_eng:		Engineering Syscon register map
+ * @syscfg:		Syscon register map
  */
 static struct sti_cpufreq_ddata {
 	struct device *cpu;