mtd: nand: denali: remove unneeded <linux/slab.h> includes

The driver calls devm_kzalloc()/devm_kfree() to allocate/free memory.
They are declared in <linux/device.h>, not in <linux/slab.h>.

Signed-off-by: Masahiro Yamada <[e-mail]>
Reviewed-by: Marek Vasut <[e-mail]>
Signed-off-by: Boris Brezillon <[e-mail]>

drivers/mtd/nand/denali.c

···
 #include <linux/dma-mapping.h>
 #include <linux/wait.h>
 #include <linux/mutex.h>
-#include <linux/slab.h>
 #include <linux/mtd/mtd.h>
 #include <linux/module.h>
 

drivers/mtd/nand/denali_dt.c

···
 #include <linux/platform_device.h>
 #include <linux/of.h>
 #include <linux/of_device.h>
-#include <linux/slab.h>
 
 #include "denali.h"
 

drivers/mtd/nand/denali_pci.c

···
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/pci.h>
-#include <linux/slab.h>
 
 #include "denali.h"