oprofile: Remove exit function for timer mode

Remove exit functions by moving init/exit code to oprofile's setup/
shutdown functions. Doing so the oprofile module exit code will be
easier and less error-prone.

Signed-off-by: Robert Richter <robert.richter@amd.com>
diff --git a/drivers/oprofile/oprof.c b/drivers/oprofile/oprof.c
index f8c752e..f7cd069 100644
--- a/drivers/oprofile/oprof.c
+++ b/drivers/oprofile/oprof.c
@@ -262,9 +262,7 @@
 		return 0;
 
 	/* failed */
-	if (timer_mode)
-		oprofile_timer_exit();
-	else
+	if (!timer_mode)
 		oprofile_arch_exit();
 
 	return err;
@@ -274,9 +272,7 @@
 static void __exit oprofile_exit(void)
 {
 	oprofilefs_unregister();
-	if (timer_mode)
-		oprofile_timer_exit();
-	else
+	if (!timer_mode)
 		oprofile_arch_exit();
 }