Bluetooth: btmrvl: drop duplicate header slab.h

Drop duplicate header slab.h from btmrvl_drv.h.
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

drivers/bluetooth/btmrvl_drv.h

@@ -32,7 +32,6 @@
 #include <linux/of_platform.h>
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
-#include <linux/slab.h>
 #include <linux/of_irq.h>
 
 #define BTM_HEADER_LEN			4