staging: comedi: mite: move #include <linux/slab.h>

The Comedi driver modules build fine if the inclusion of <linux/slab.h>
is removed from "mite.h", so remove it.  However, since "mite.c" calls
`kzalloc()`, include <linux/slab.h> there.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/drivers/mite.c

@@ -47,6 +47,7 @@
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
 #include <linux/module.h>
+#include <linux/slab.h>
 
 #include "../comedi_pci.h"
 

drivers/staging/comedi/drivers/mite.h

@@ -20,7 +20,6 @@
 #define _MITE_H_
 
 #include <linux/log2.h>
-#include <linux/slab.h>
 #include "../comedi_pci.h"
 
 #define PCIMIO_COMPAT