libnvdimm: Remove duplicate struct declaration

struct device is declared at 133rd line. The second declaration is
unnecessary, remove it.
Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
Link: https://lore.kernel.org/r/20210419112725.42145-1-wanjiabing@vivo.comSigned-off-by: Dan Williams <dan.j.williams@intel.com>

include/linux/libnvdimm.h

@@ -141,7 +141,6 @@ static inline void __iomem *devm_nvdimm_ioremap(struct device *dev,
 
 struct nvdimm_bus;
 struct module;
-struct device;
 struct nd_blk_region;
 struct nd_blk_region_desc {
 	int (*enable)(struct nvdimm_bus *nvdimm_bus, struct device *dev);