mfd: cs42l43: Tidy up header includes

Use more forward declarations, move header guards to cover other
includes, and rely less on including headers through other headers.

Suggested-by: Andy Shevchenko <[e-mail]>
Signed-off-by: Charles Keepax <[e-mail]>
Reviewed-by: Andy Shevchenko <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Lee Jones <[e-mail]>

drivers/mfd/cs42l43-i2c.c

···
  *                         Cirrus Logic International Semiconductor Ltd.
  */
 
+#include <linux/array_size.h>
 #include <linux/err.h>
-#include <linux/errno.h>
 #include <linux/i2c.h>
+#include <linux/mfd/cs42l43.h>
 #include <linux/mfd/cs42l43-regs.h>
+#include <linux/mod_devicetable.h>
 #include <linux/module.h>
+#include <linux/pm.h>
+#include <linux/regmap.h>
 
 #include "cs42l43.h"
 

drivers/mfd/cs42l43-sdw.c

···
  *                         Cirrus Logic International Semiconductor Ltd.
  */
 
+#include <linux/array_size.h>
 #include <linux/device.h>
 #include <linux/err.h>
-#include <linux/errno.h>
+#include <linux/mfd/cs42l43.h>
 #include <linux/mfd/cs42l43-regs.h>
+#include <linux/mod_devicetable.h>
 #include <linux/module.h>
+#include <linux/pm.h>
+#include <linux/regmap.h>
 #include <linux/soundwire/sdw.h>
 #include <linux/soundwire/sdw_registers.h>
 #include <linux/soundwire/sdw_type.h>

drivers/mfd/cs42l43.c

···
  *                         Cirrus Logic International Semiconductor Ltd.
  */
 
+#include <linux/array_size.h>
 #include <linux/bitops.h>
 #include <linux/build_bug.h>
 #include <linux/delay.h>
+#include <linux/device.h>
 #include <linux/err.h>
-#include <linux/errno.h>
 #include <linux/firmware.h>
+#include <linux/gpio/consumer.h>
 #include <linux/jiffies.h>
 #include <linux/mfd/core.h>
+#include <linux/mfd/cs42l43.h>
 #include <linux/mfd/cs42l43-regs.h>
 #include <linux/module.h>
+#include <linux/pm.h>
 #include <linux/pm_runtime.h>
+#include <linux/regmap.h>
 #include <linux/soundwire/sdw.h>
+#include <linux/types.h>
 
 #include "cs42l43.h"
 

drivers/mfd/cs42l43.h

···
  *                         Cirrus Logic International Semiconductor Ltd.
  */
 
-#include <linux/mfd/cs42l43.h>
-#include <linux/pm.h>
-#include <linux/regmap.h>
-
 #ifndef CS42L43_CORE_INT_H
 #define CS42L43_CORE_INT_H
 
 #define CS42L43_N_DEFAULTS 176
+
+struct dev_pm_ops;
+struct device;
+struct reg_default;
+
+struct cs42l43;
 
 extern const struct dev_pm_ops cs42l43_pm_ops;
 extern const struct reg_default cs42l43_reg_default[CS42L43_N_DEFAULTS];

include/linux/mfd/cs42l43.h

···
  *                         Cirrus Logic International Semiconductor Ltd.
  */
 
-#include <linux/completion.h>
-#include <linux/device.h>
-#include <linux/gpio/consumer.h>
-#include <linux/mutex.h>
-#include <linux/regmap.h>
-#include <linux/regulator/consumer.h>
-#include <linux/soundwire/sdw.h>
-#include <linux/workqueue.h>
-
 #ifndef CS42L43_CORE_EXT_H
 #define CS42L43_CORE_EXT_H
 
+#include <linux/completion.h>
+#include <linux/mutex.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
+#include <linux/workqueue.h>
+
 #define CS42L43_N_SUPPLIES		3
+
+struct device;
+struct gpio_desc;
+struct sdw_slave;
 
 enum cs42l43_irq_numbers {
 	CS42L43_PLL_LOST_LOCK,