Update SUMMARY.md

SUMMARY.md

@@ -18,8 +18,8 @@
     * [Memblock](mm/linux-mm-1.md)
 * [Data Structures in the Linux Kernel](DataStructures/README.md)
     * [Doubly linked list](DataStructures/dlist.md)
-* [Concepts](Conecpts/README.md)
-    * [Per-CPU variables](Conecpts/per-cpu.md)
+* [Concepts](Concepts/README.md)
+    * [Per-CPU variables](Concepts/per-cpu.md)
     * [Cpumasks]()
 * [Theory](Theory/README.md)
     * [Paging](Theory/Paging.md)