clk: export __clk_get_flags for modular clock providers

The common clock api provides some helpers for clk-providers but does
not export these helpers. This hinders clk-providers to be built as modules.
This patch adds __clk_get_flags() to the list of exported symbols.
Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>

drivers/clk/clk.c

@@ -458,6 +458,7 @@ static void clk_unprepare_unused_subtree(struct clk *clk)
 			clk->ops->unprepare(clk->hw);
 	}
 }
+EXPORT_SYMBOL_GPL(__clk_get_flags);
 
 /* caller must hold prepare_lock */
 static void clk_disable_unused_subtree(struct clk *clk)