arm64: mm: Remove pte_unmap_nested()

As of commit ece0e2b6 ("mm: remove pte_*map_nested()"),
pte_unmap_nested() is no longer used and can be removed from the arm64
code.
Signed-off-by: Qian Cai <cai@lca.pw>
[will: also remove pte_offset_map_nested()]
Signed-off-by: Will Deacon <will.deacon@arm.com>

arch/arm64/include/asm/pgtable.h

@@ -487,8 +487,6 @@ static inline void pte_unmap(pte_t *pte) { }
 #define pte_offset_kernel(dir,addr)	((pte_t *)__va(pte_offset_phys((dir), (addr))))
 
 #define pte_offset_map(dir,addr)	pte_offset_kernel((dir), (addr))
-#define pte_offset_map_nested(dir,addr)	pte_offset_kernel((dir), (addr))
-#define pte_unmap_nested(pte)		do { } while (0)
 
 #define pte_set_fixmap(addr)		((pte_t *)set_fixmap_offset(FIX_PTE, addr))
 #define pte_set_fixmap_offset(pmd, addr)	pte_set_fixmap(pte_offset_phys(pmd, addr))