drivers/video/fbdev/fb-puv3.c: Add header files for function unifb_mmap

drivers/video/fbdev/fb-puv3.c: Add header files for function unifb_mmap

Function unifb_mmap calls functions which are defined in linux/mm.h
and asm/pgtable.h

The related error (for unicore32 with unicore32_defconfig):
	CC      drivers/video/fbdev/fb-puv3.o
	drivers/video/fbdev/fb-puv3.c: In function 'unifb_mmap':
	drivers/video/fbdev/fb-puv3.c:646: error: implicit declaration of
				      function 'vm_iomap_memory'
	drivers/video/fbdev/fb-puv3.c:646: error: implicit declaration of
				      function 'pgprot_noncached'

Signed-off-by: Zhichuang Sun <[email protected]>
Cc: Jean-Christophe Plagniol-Villard <[email protected]>
Cc: Tomi Valkeinen <[email protected]>
Cc: Jingoo Han <[email protected]>
Cc: Daniel Vetter <[email protected]>
Cc: Joe Perches <[email protected]>
Cc: Laurent Pinchart <[email protected]>
Cc: [email protected]
Acked-by: Xuetao Guan <[email protected]>
Signed-off-by: Tomi Valkeinen <[email protected]>