arm64/mm: Unify CONT_PTE_SHIFT

CONT_PTE_SHIFT actually depends on CONFIG_ARM64_CONT_SHIFT. It's
reasonable to reflect the dependency:

* This renames CONFIG_ARM64_CONT_SHIFT to CONFIG_ARM64_CONT_PTE_SHIFT,
so that we can introduce CONFIG_ARM64_CONT_PMD_SHIFT later.

* CONT_{SHIFT, SIZE, MASK}, defined in page-def.h are removed as they
are not used by anyone.

* CONT_PTE_SHIFT is determined by CONFIG_ARM64_CONT_PTE_SHIFT.

Signed-off-by: Gavin Shan <[e-mail]>
Reviewed-by: Anshuman Khandual <[e-mail]>
Acked-by: Catalin Marinas <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Will Deacon <[e-mail]>

arch/arm64/Kconfig

···
 	default 14 if ARM64_16K_PAGES
 	default 12
 
-config ARM64_CONT_SHIFT
+config ARM64_CONT_PTE_SHIFT
 	int
 	default 5 if ARM64_64K_PAGES
 	default 7 if ARM64_16K_PAGES

arch/arm64/include/asm/page-def.h

···
 #include <linux/const.h>
 
 /* PAGE_SHIFT determines the page size */
-/* CONT_SHIFT determines the number of pages which can be tracked together  */
 #define PAGE_SHIFT		CONFIG_ARM64_PAGE_SHIFT
-#define CONT_SHIFT		CONFIG_ARM64_CONT_SHIFT
 #define PAGE_SIZE		(_AC(1, UL) << PAGE_SHIFT)
 #define PAGE_MASK		(~(PAGE_SIZE-1))
-
-#define CONT_SIZE		(_AC(1, UL) << (CONT_SHIFT + PAGE_SHIFT))
-#define CONT_MASK		(~(CONT_SIZE-1))
 
 #endif /* __ASM_PAGE_DEF_H */

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

···
 /*
  * Contiguous page definitions.
  */
+#define CONT_PTE_SHIFT		(CONFIG_ARM64_CONT_PTE_SHIFT + PAGE_SHIFT)
 #ifdef CONFIG_ARM64_64K_PAGES
-#define CONT_PTE_SHIFT		(5 + PAGE_SHIFT)
 #define CONT_PMD_SHIFT		(5 + PMD_SHIFT)
 #elif defined(CONFIG_ARM64_16K_PAGES)
-#define CONT_PTE_SHIFT		(7 + PAGE_SHIFT)
 #define CONT_PMD_SHIFT		(5 + PMD_SHIFT)
 #else
-#define CONT_PTE_SHIFT		(4 + PAGE_SHIFT)
 #define CONT_PMD_SHIFT		(4 + PMD_SHIFT)
 #endif