f2fs: use f2fs_radix_tree_insert to clean codes

No modification in functionality, just clean codes with f2fs_radix_tree_insert.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
index 40887d3..67860b6 100644
--- a/fs/f2fs/gc.c
+++ b/fs/f2fs/gc.c
@@ -356,11 +356,8 @@
 	}
 	new_ie = f2fs_kmem_cache_alloc(inode_entry_slab, GFP_NOFS);
 	new_ie->inode = inode;
-retry:
-	if (radix_tree_insert(&gc_list->iroot, inode->i_ino, new_ie)) {
-		cond_resched();
-		goto retry;
-	}
+
+	f2fs_radix_tree_insert(&gc_list->iroot, inode->i_ino, new_ie);
 	list_add_tail(&new_ie->list, &gc_list->ilist);
 }