oprofile: rename kernel-wide identifiers

This patch renames kernel-wide identifiers to something more oprofile
specific names.

Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Robert Richter <robert.richter@amd.com>
diff --git a/drivers/oprofile/event_buffer.c b/drivers/oprofile/event_buffer.c
index 191a320..2b7ae36 100644
--- a/drivers/oprofile/event_buffer.c
+++ b/drivers/oprofile/event_buffer.c
@@ -73,8 +73,8 @@
 	unsigned long flags;
 
 	spin_lock_irqsave(&oprofilefs_lock, flags);
-	buffer_size = fs_buffer_size;
-	buffer_watershed = fs_buffer_watershed;
+	buffer_size = oprofile_buffer_size;
+	buffer_watershed = oprofile_buffer_watershed;
 	spin_unlock_irqrestore(&oprofilefs_lock, flags);
 
 	if (buffer_watershed >= buffer_size)