i2c: core: Export bus recovery functions

Current -next fails to link an ARM allmodconfig because drivers that use
the core recovery functions can be built as modules but those functions
are not exported:

ERROR: "i2c_generic_gpio_recovery" [drivers/i2c/busses/i2c-davinci.ko] undefined!
ERROR: "i2c_generic_scl_recovery" [drivers/i2c/busses/i2c-davinci.ko] undefined!
ERROR: "i2c_recover_bus" [drivers/i2c/busses/i2c-davinci.ko] undefined!

Add exports to fix this.

Fixes: 5f9296ba21b3c (i2c: Add bus recovery infrastructure)
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

drivers/i2c/i2c-core.c

@@ -596,6 +596,7 @@ int i2c_generic_scl_recovery(struct i2c_adapter *adap)
 	adap->bus_recovery_info->set_scl(adap, 1);
 	return i2c_generic_recovery(adap);
 }
+EXPORT_SYMBOL_GPL(i2c_generic_scl_recovery);
 
 int i2c_generic_gpio_recovery(struct i2c_adapter *adap)
 {
@@ -610,6 +611,7 @@ int i2c_generic_gpio_recovery(struct i2c_adapter *adap)
 
 	return ret;
 }
+EXPORT_SYMBOL_GPL(i2c_generic_gpio_recovery);
 
 int i2c_recover_bus(struct i2c_adapter *adap)
 {
@@ -619,6 +621,7 @@ int i2c_recover_bus(struct i2c_adapter *adap)
 	dev_dbg(&adap->dev, "Trying i2c bus recovery\n");
 	return adap->bus_recovery_info->recover_bus(adap);
 }
+EXPORT_SYMBOL_GPL(i2c_recover_bus);
 
 static int i2c_device_probe(struct device *dev)
 {