arm64/mm: Remove CONT_RANGE_OFFSET

The macro was introduced by commit <ecf35a237a85> ("arm64: PTE/PMD
contiguous bit definition") at the beginning. It's only used by
commit <348a65cdcbbf> ("arm64: Mark kernel page ranges contiguous"),
which was reverted later by commit <667c27597ca8>. This makes the
macro unused.

This removes the unused macro (CONT_RANGE_OFFSET).

Signed-off-by: Gavin Shan <gshan@redhat.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20200910095936.20307-1-gshan@redhat.com
Signed-off-by: Will Deacon <will@kernel.org>

Author: Gavin Shan

arch/arm64/include/asm/pgtable-hwdef.h

@@ -98,8 +98,6 @@
 #define CONT_PMDS		(1 << (CONT_PMD_SHIFT - PMD_SHIFT))
 #define CONT_PMD_SIZE		(CONT_PMDS * PMD_SIZE)
 #define CONT_PMD_MASK		(~(CONT_PMD_SIZE - 1))
-/* the numerical offset of the PTE within a range of CONT_PTES */
-#define CONT_RANGE_OFFSET(addr) (((addr)>>PAGE_SHIFT)&(CONT_PTES-1))
 
 /*
  * Hardware page table definitions.