staging: lustre: clean function declarations in class_obd.c up

We get 2 warnings when building kernel with W=1:

drivers/staging/lustre/lustre/obdclass/linux/linux-module.c:413:5: warning: no previous prototype for 'class_procfs_init' [-Wmissing-prototypes]
drivers/staging/lustre/lustre/obdclass/linux/linux-module.c:449:5: warning: no previous prototype for 'class_procfs_clean' [-Wmissing-prototypes]

In fact, both functions are declared in
drivers/staging/lustre/lustre/obdclass/class_obd.c,but should be
declared in a header file, thus can be recognized in other file.

So this patch moves the declarations into
drivers/staging/lustre/lustre/include/obd_class.h.
Signed-off-by: Baoyou Xie <baoyou.xie@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/lustre/lustre/include/obd_class.h

@@ -1716,6 +1716,8 @@ void class_exit_uuidlist(void);
 extern char obd_jobid_node[];
 extern struct miscdevice obd_psdev;
 extern spinlock_t obd_types_lock;
+int class_procfs_init(void);
+int class_procfs_clean(void);
 
 /* prng.c */
 #define ll_generate_random_uuid(uuid_out) cfs_get_random_bytes(uuid_out, sizeof(class_uuid_t))

drivers/staging/lustre/lustre/obdclass/class_obd.c

@@ -446,9 +446,6 @@ static int obd_init_checks(void)
 	return ret;
 }
 
-extern int class_procfs_init(void);
-extern int class_procfs_clean(void);
-
 static int __init obdclass_init(void)
 {
 	int i, err;