Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/ia64/kernel/unwind.c b/arch/ia64/kernel/unwind.c
index e04efa0..7601fe0 100644
--- a/arch/ia64/kernel/unwind.c
+++ b/arch/ia64/kernel/unwind.c
@@ -28,7 +28,7 @@
  *	  acquired, then the read-write lock must be acquired first.
  */
 #include <linux/module.h>
-#include <linux/bootmem.h>
+#include <linux/memblock.h>
 #include <linux/elf.h>
 #include <linux/kernel.h>
 #include <linux/sched.h>