i2c: designware: Make dw_readl() and dw_writel() static

dw_readl() and dw_writel() are not used outside of i2c-designware-core and
they are not exported so make them static and remove their forward
declaration.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

drivers/i2c/busses/i2c-designware-core.c

@@ -165,7 +165,7 @@ static char *abort_sources[] = {
 		"lost arbitration",
 };
 
-u32 dw_readl(struct dw_i2c_dev *dev, int offset)
+static u32 dw_readl(struct dw_i2c_dev *dev, int offset)
 {
 	u32 value;
 
@@ -181,7 +181,7 @@ u32 dw_readl(struct dw_i2c_dev *dev, int offset)
 		return value;
 }
 
-void dw_writel(struct dw_i2c_dev *dev, u32 b, int offset)
+static void dw_writel(struct dw_i2c_dev *dev, u32 b, int offset)
 {
 	if (dev->accessor_flags & ACCESS_SWAP)
 		b = swab32(b);

drivers/i2c/busses/i2c-designware-core.h

@@ -112,8 +112,6 @@ struct dw_i2c_dev {
 #define ACCESS_SWAP		0x00000001
 #define ACCESS_16BIT		0x00000002
 
-extern u32 dw_readl(struct dw_i2c_dev *dev, int offset);
-extern void dw_writel(struct dw_i2c_dev *dev, u32 b, int offset);
 extern int i2c_dw_init(struct dw_i2c_dev *dev);
 extern int i2c_dw_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[],
 		int num);