csky: Fixup _PAGE_GLOBAL bit for 610 tlb entry

C-SKY CPU 8xx's _PAGE_GLOBAL is BIT(0), but 610's _PAGE_GLOBAL is
BIT(6). Use _PAGE_GLOBAL macro instead of bad magic number.
Signed-off-by: Guo Ren <ren_guo@c-sky.com>

arch/csky/include/asm/pgtable.h

@@ -45,8 +45,8 @@
 	((pte_t *)page_address(pmd_page(*(dir))) + __pte_offset_t(address))
 #define pmd_page(pmd)	(pfn_to_page(pmd_phys(pmd) >> PAGE_SHIFT))
 #define pte_clear(mm, addr, ptep)	set_pte((ptep), \
-			(((unsigned int)addr&0x80000000)?__pte(1):__pte(0)))
-#define pte_none(pte)	(!(pte_val(pte)&0xfffffffe))
+	(((unsigned int) addr & PAGE_OFFSET) ? __pte(_PAGE_GLOBAL) : __pte(0)))
+#define pte_none(pte)		(!(pte_val(pte) & ~_PAGE_GLOBAL))
 #define pte_present(pte)	(pte_val(pte) & _PAGE_PRESENT)
 #define pte_pfn(x)	((unsigned long)((x).pte_low >> PAGE_SHIFT))
 #define pfn_pte(pfn, prot) __pte(((unsigned long long)(pfn) << PAGE_SHIFT) \