cpufreq: OMAP: Fix compilation error 'r & ret undeclared'

With a recent change "d4019f0a cpufreq: move freq change notifications to cpufreq
core" few variables (r & ret) are removed by mistake and hence these warnings:

drivers/cpufreq/omap-cpufreq.c: In function omap_target:
drivers/cpufreq/omap-cpufreq.c:64:2: error: ret undeclared (first use in this function)
drivers/cpufreq/omap-cpufreq.c:64:2: note: each undeclared identifier is reported only once for each function it appears in
drivers/cpufreq/omap-cpufreq.c:94:3: error: r undeclared (first use in this function)
drivers/cpufreq/omap-cpufreq.c:116:1: warning: control reaches end of non-void function [-Wreturn-type]

Lets fix them by declaring those variables again.

Fixes: d4019f0a (cpufreq: move freq change notifications to cpufreq core)
Reported-by: NSebastian Capella <sebastian.capella@linaro.org>
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/cpufreq/omap-cpufreq.c

@@ -53,6 +53,7 @@ static unsigned int omap_getspeed(unsigned int cpu)
 
 static int omap_target(struct cpufreq_policy *policy, unsigned int index)
 {
+	int r, ret;
 	struct dev_pm_opp *opp;
 	unsigned long freq, volt = 0, volt_old = 0, tol = 0;
 	unsigned int old_freq, new_freq;