arch/unicore32/kernel/setup.c: add generic 'screen_info' to avoid compiling failure

Add generic 'screen_info' just like another architectures have done
(e.g. tile, sh, score, ia64, hexagon, and cris).

The related error (with allmodconfig under unicore32):

    LD      init/built-in.o
  drivers/built-in.o: In function `vgacon_save_screen':
  powercap_sys.c:(.text+0x21788): undefined reference to `screen_info'
  drivers/built-in.o: In function `vgacon_resize':
  powercap_sys.c:(.text+0x21b54): undefined reference to `screen_info'
  drivers/built-in.o: In function `vgacon_switch':
  powercap_sys.c:(.text+0x21cb4): undefined reference to `screen_info'
  drivers/built-in.o: In function `vgacon_init':
  powercap_sys.c:(.text+0x2296c): undefined reference to `screen_info'
  drivers/built-in.o: In function `vgacon_startup':
  powercap_sys.c:(.text+0x22e80): undefined reference to `screen_info'

Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
Acked-by: Xuetao Guan <gxt@mprc.pku.edu.cn>
unicore32: include: asm: add missing ')' for PAGE_* macros in pgtable.h

Missing related ')', the related compiling error:

    CC [M]  drivers/gpu/drm/udl/udl_fb.o
  drivers/gpu/drm/udl/udl_fb.c: In function Â‘udl_fb_mmapÂ’:
  drivers/gpu/drm/udl/udl_fb.c:273: error: expected Â‘)Â’ before Â‘returnÂ’
  drivers/gpu/drm/udl/udl_fb.c:281: error: expected expression before Â‘}Â’ token
  make[4]: *** [drivers/gpu/drm/udl/udl_fb.o] Error 1
  make[3]: *** [drivers/gpu/drm/udl] Error 2
  make[2]: *** [drivers/gpu/drm] Error 2
  make[1]: *** [drivers/gpu] Error 2
  make: *** [drivers] Error 2

Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
Acked-by: Xuetao Guan <gxt@mprc.pku.edu.cn>
arch:unicore32:mm: add devmem_is_allowed() to support STRICT_DEVMEM

unicore32 supports STRICT_DEVMEM, so it needs devmem_is_allowed(), like
some of other architectures have done (e.g. arm, powerpc, x86 ...).

The related error with allmodconfig:

    CC      drivers/char/mem.o
  drivers/char/mem.c: In function ârange_is_allowedâ:
  drivers/char/mem.c:69: error: implicit declaration of function âdevmem_is_allowedâ
  make[2]: *** [drivers/char/mem.o] Error 1
  make[1]: *** [drivers/char] Error 2
  make: *** [drivers] Error 2

Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
Acked-by: Xuetao Guan <gxt@mprc.pku.edu.cn>