clk: add DT fixed-clock binding support

Add support for DT "fixed-clock" binding to the common fixed rate clock
support.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
[Rob Herring] Rework and move into common clock infrastructure
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h
index 7c9c691..77335fa 100644
--- a/include/linux/clk-provider.h
+++ b/include/linux/clk-provider.h
@@ -172,6 +172,8 @@
 		const char *parent_name, unsigned long flags,
 		unsigned long fixed_rate);
 
+void of_fixed_clk_setup(struct device_node *np);
+
 /**
  * struct clk_gate - gating clock
  *