mx51: Fix USB PHY clocks

The i.MX51 has a single USB PHY clock, while the i.MX53 has two. These 3 clocks
have different clock gate control bit-fields.

The existing code was correct only for i.MX53, so this patch fixes the i.MX51
use case.

Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
Cc: Stefano Babic <sbabic@denx.de>
Cc: Marek Vasut <marex@denx.de>
Cc: Jana Rapava <fermata7@gmail.com>
Cc: Wolfgang Grandegger <wg@denx.de>
Cc: Igor Grinberg <grinberg@compulab.co.il>
diff --git a/arch/arm/include/asm/arch-mx5/clock.h b/arch/arm/include/asm/arch-mx5/clock.h
index 82c5b1a..83fb877 100644
--- a/arch/arm/include/asm/arch-mx5/clock.h
+++ b/arch/arm/include/asm/arch-mx5/clock.h
@@ -57,7 +57,8 @@
 u32 imx_get_fecclk(void);
 unsigned int mxc_get_clock(enum mxc_clock clk);
 int mxc_set_clock(u32 ref, u32 freq, u32 clk_type);
-void set_usb_phy2_clk(void);
+void set_usb_phy_clk(void);
+void enable_usb_phy1_clk(unsigned char enable);
 void enable_usb_phy2_clk(unsigned char enable);
 void set_usboh3_clk(void);
 void enable_usboh3_clk(unsigned char enable);