percpu: remove PERCPU_ENOUGH_ROOM which is stale definition

As pure cleanup, this patch removes PERCPU_ENOUGH_ROOM which is not
used any more. That is, no code refers to the definition.
Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Jungseok Lee <jungseoklee85@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

arch/ia64/include/asm/percpu.h

@@ -6,8 +6,6 @@
  *	David Mosberger-Tang <davidm@hpl.hp.com>
  */
 
-#define PERCPU_ENOUGH_ROOM PERCPU_PAGE_SIZE
-
 #ifdef __ASSEMBLY__
 # define THIS_CPU(var)	(var)  /* use this to mark accesses to per-CPU variables... */
 #else /* !__ASSEMBLY__ */

include/linux/percpu.h

@@ -18,12 +18,6 @@
 #define PERCPU_MODULE_RESERVE		0
 #endif
 
-#ifndef PERCPU_ENOUGH_ROOM
-#define PERCPU_ENOUGH_ROOM						\
-	(ALIGN(__per_cpu_end - __per_cpu_start, SMP_CACHE_BYTES) +	\
-	 PERCPU_MODULE_RESERVE)
-#endif
-
 /* minimum unit size, also is the maximum supported allocation size */
 #define PCPU_MIN_UNIT_SIZE		PFN_ALIGN(32 << 10)