tkernel: export some symbols for the kill block feature

The kill block feature whil compile as a module, and requires
the following symbols:
 - cpu_cgrp_subsys
 - kernfs_name

Signed-off-by: Yongliang Gao <leonylgao@tencent.com>
Reviewed-by: Jianping Liu <frankjpliu@tencent.com>

fs/kernfs/dir.c

@@ -203,6 +203,7 @@ int kernfs_name(struct kernfs_node *kn, char *buf, size_t buflen)
 	read_unlock_irqrestore(&kernfs_rename_lock, flags);
 	return ret;
 }
+EXPORT_SYMBOL_GPL(kernfs_name);
 
 /**
  * kernfs_path_from_node - build path of node @to relative to @from.

kernel/sched/core.c

@@ -11845,6 +11845,7 @@ struct cgroup_subsys cpu_cgrp_subsys = {
 	.early_init	= true,
 	.threaded	= true,
 };
+EXPORT_SYMBOL_GPL(cpu_cgrp_subsys);
 
 #endif	/* CONFIG_CGROUP_SCHED */