[PATCH -next] driver core: fix build for CONFIG_BLOCK=n

[Randy Dunlap <randy.dunlap@oracle.com>]

From: Randy Dunlap <randy.dunlap@oracle.com>

Fix build when CONFIG_BLOCK is not enabled (since SEP-06).
Fixes these build errors:

drivers/base/core.c: In function 'get_device_parent':
drivers/base/core.c:622: error: 'block_class' undeclared (first use in this function)
drivers/base/core.c: In function 'device_add_class_symlinks':
drivers/base/core.c:712: error: 'block_class' undeclared (first use in this function)
drivers/base/core.c: In function 'device_remove_class_symlinks':
drivers/base/core.c:742: error: 'block_class' undeclared (first use in this function)

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
---
 drivers/base/core.c |    6 ++++++
 1 file changed, 6 insertions(+)

--- linux-next-20100920.orig/drivers/base/core.c
+++ linux-next-20100920/drivers/base/core.c
@@ -618,6 +618,7 @@ static struct kobject *get_device_parent
 		struct kobject *k;
 
 #ifdef CONFIG_SYSFS_DEPRECATED
+#ifdef CONFIG_BLOCK
 		/* block disks show up in /sys/block */
 		if (dev->class == &block_class) {
 			if (parent && parent->class == &block_class)
@@ -625,6 +626,7 @@ static struct kobject *get_device_parent
 			return &block_class.p->class_subsys.kobj;
 		}
 #endif
+#endif
 		/*
 		 * If we have no parent, we live in "virtual".
 		 * Class-devices with a non class-device as parent, live
@@ -708,10 +710,12 @@ static int device_add_class_symlinks(str
 	}
 
 #ifdef CONFIG_SYSFS_DEPRECATED
+#ifdef CONFIG_BLOCK
 	/* /sys/block has directories and does not need symlinks */
 	if (dev->class == &block_class)
 		return 0;
 #endif
+#endif
 
 	/* link in the class directory pointing to the device */
 	error = sysfs_create_link(&dev->class->p->class_subsys.kobj,
@@ -739,9 +743,11 @@ static void device_remove_class_symlinks
 		sysfs_remove_link(&dev->kobj, "device");
 	sysfs_remove_link(&dev->kobj, "subsystem");
 #ifdef CONFIG_SYSFS_DEPRECATED
+#ifdef CONFIG_BLOCK
 	if (dev->class == &block_class)
 		return;
 #endif
+#endif
 	sysfs_delete_link(&dev->class->p->class_subsys.kobj, &dev->kobj, dev_name(dev));
 }