ARM: pgtable: remove FIRST_USER_PGD_NR

FIRST_USER_PGD_NR is now unnecessary, as this has been replaced by
FIRST_USER_ADDRESS except in the architecture code.  Fix up the last
usage of FIRST_USER_PGD_NR, and remove the definition.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h
index 1e31af2..4701a6b 100644
--- a/arch/arm/include/asm/pgtable.h
+++ b/arch/arm/include/asm/pgtable.h
@@ -138,8 +138,7 @@
  */
 #define FIRST_USER_ADDRESS	PAGE_SIZE
 
-#define FIRST_USER_PGD_NR	1
-#define USER_PTRS_PER_PGD	((TASK_SIZE/PGDIR_SIZE) - FIRST_USER_PGD_NR)
+#define USER_PTRS_PER_PGD	(TASK_SIZE / PGDIR_SIZE)
 
 /*
  * section address mask and size definitions.