clk: samsung: Modify _get_rate() helper to use __clk_lookup()

There is no need to use clkdev inside the clock driver to retrieve the
clocks for internal use. Instead __clk_lookup() helper can be used to
look up clocks by their platform name.

This patch modifies the behavior of _get_rate() helper to look up clocks
by platform name and adjusts all users of it to pass platform names
instead of clkdev aliases.

Signed-off-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
diff --git a/drivers/clk/samsung/clk.c b/drivers/clk/samsung/clk.c
index cd3c40a..f503f32 100644
--- a/drivers/clk/samsung/clk.c
+++ b/drivers/clk/samsung/clk.c
@@ -307,14 +307,12 @@
 unsigned long _get_rate(const char *clk_name)
 {
 	struct clk *clk;
-	unsigned long rate;
 
-	clk = clk_get(NULL, clk_name);
-	if (IS_ERR(clk)) {
+	clk = __clk_lookup(clk_name);
+	if (!clk) {
 		pr_err("%s: could not find clock %s\n", __func__, clk_name);
 		return 0;
 	}
-	rate = clk_get_rate(clk);
-	clk_put(clk);
-	return rate;
+
+	return clk_get_rate(clk);
 }