clk: at91: utmi: Set the reference clock frequency

By default, it is assumed that the UTMI clock is generated from
a 12 MHz reference clock (MAINCK). If it's not the case, the FREQ
field of the SFR_UTMICKTRIM has to be updated to generate the UTMI
clock in the proper way.

The UTMI clock has a fixed rate of 480 MHz. In fact, there is no
multiplier we can configure. The multiplier is managed internally,
depending on the reference clock frequency, to achieve the target
of 480 MHz.

The patch is cloned from the patch of mailing-list:
	[PATCH v2] clk: at91: utmi: set the mainck rate

Signed-off-by: Wenyou Yang <wenyou.yang@microchip.com>
[trini: Depend on SPL_DM]
Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/drivers/clk/at91/pmc.h b/drivers/clk/at91/pmc.h
index bd3caba..5abda76 100644
--- a/drivers/clk/at91/pmc.h
+++ b/drivers/clk/at91/pmc.h
@@ -8,8 +8,11 @@
 #ifndef __AT91_PMC_H__
 #define __AT91_PMC_H__
 
+#include <regmap.h>
+
 struct pmc_platdata {
 	struct at91_pmc *reg_base;
+	struct regmap *regmap_sfr;
 };
 
 int at91_pmc_core_probe(struct udevice *dev);