i2c: completion header cleanups

i2c-core and i2c-isa use completions without including
<linux/completion.h>. Fix it.

i2c-powermac includes <linux/completion.h> but doesn't use any
completion. Fix it.
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Brownell <david-b@pacbell.net>

drivers/i2c/busses/i2c-isa.c

@@ -39,6 +39,7 @@
 #include <linux/i2c.h>
 #include <linux/i2c-isa.h>
 #include <linux/platform_device.h>
+#include <linux/completion.h>
 
 static u32 isa_func(struct i2c_adapter *adapter);
 

drivers/i2c/busses/i2c-powermac.c

@@ -25,7 +25,6 @@
 #include <linux/types.h>
 #include <linux/i2c.h>
 #include <linux/init.h>
-#include <linux/completion.h>
 #include <linux/device.h>
 #include <linux/platform_device.h>
 #include <asm/prom.h>

drivers/i2c/i2c-core.c

@@ -32,6 +32,7 @@
 #include <linux/seq_file.h>
 #include <linux/platform_device.h>
 #include <linux/mutex.h>
+#include <linux/completion.h>
 #include <asm/uaccess.h>