kill FIRST_USER_PGD_NR

dead since 2005, time to bury the body...

Reviewed-by: Michal Simek <michal.simek@amd.com> # microblaze
Reviewed-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Author: Al Viro

arch/microblaze/include/asm/pgtable.h

@@ -99,7 +99,6 @@ extern pte_t *va_to_pte(unsigned long address);
 #define PTRS_PER_PGD	(1 << (32 - PGDIR_SHIFT))
 
 #define USER_PTRS_PER_PGD	(TASK_SIZE / PGDIR_SIZE)
-#define FIRST_USER_PGD_NR	0
 
 #define USER_PGD_PTRS (PAGE_OFFSET >> PGDIR_SHIFT)
 #define KERNEL_PGD_PTRS (PTRS_PER_PGD-USER_PGD_PTRS)

arch/xtensa/include/asm/pgtable.h

@@ -58,7 +58,6 @@
 #define PTRS_PER_PTE_SHIFT	10
 #define PTRS_PER_PGD		1024
 #define USER_PTRS_PER_PGD	(TASK_SIZE/PGDIR_SIZE)
-#define FIRST_USER_PGD_NR	(FIRST_USER_ADDRESS >> PGDIR_SHIFT)
 
 #ifdef CONFIG_MMU
 /*