i2c: designware_i2c: Move dw_i2c_speed_config to header

This is used to store the speed information for a bus. We want to provide
this to ACPI so that it can tell the kernel. Move this struct to the
header file so it can be accessed by the ACPI i2c implementation being
added later.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/i2c/designware_i2c.h b/drivers/i2c/designware_i2c.h
index 3db63b5..2027a91 100644
--- a/drivers/i2c/designware_i2c.h
+++ b/drivers/i2c/designware_i2c.h
@@ -157,6 +157,23 @@
 };
 
 /**
+ * struct dw_i2c_speed_config - timings to use for a particular speed
+ *
+ * This holds calculated values to be written to the I2C controller. Each value
+ * is represented as a number of IC clock cycles.
+ *
+ * @scl_lcnt: Low count value for SCL
+ * @scl_hcnt: High count value for SCL
+ * @sda_hold: Data hold count
+ */
+struct dw_i2c_speed_config {
+	/* SCL high and low period count */
+	u16 scl_lcnt;
+	u16 scl_hcnt;
+	u32 sda_hold;
+};
+
+/**
  * struct dw_i2c - private information for the bus
  *
  * @regs: Registers pointer