clk: Export clk_bulk_prepare()

Allow clk_bulk_prepare() to be referenced by kernel modules by adding
the missing EXPORT_SYMBOL_GPL().

Fixes: 266e4e9d9150 ("clk: add clk_bulk_get accessories")
Reported-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

drivers/clk/clk-bulk.c

@@ -105,6 +105,7 @@ err:
 
 	return  ret;
 }
+EXPORT_SYMBOL_GPL(clk_bulk_prepare);
 
 #endif /* CONFIG_HAVE_CLK_PREPARE */