Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/x86/kernel/process.h b/arch/x86/kernel/process.h
index 898e97c..1d0797b 100644
--- a/arch/x86/kernel/process.h
+++ b/arch/x86/kernel/process.h
@@ -1,4 +1,4 @@
-// SPDX-License-Identifier: GPL-2.0
+/* SPDX-License-Identifier: GPL-2.0 */
 //
 // Code shared between 32 and 64 bit
 
@@ -19,7 +19,7 @@
 	if (IS_ENABLED(CONFIG_SMP)) {
 		/*
 		 * Avoid __switch_to_xtra() invocation when conditional
-		 * STIPB is disabled and the only different bit is
+		 * STIBP is disabled and the only different bit is
 		 * TIF_SPEC_IB. For CONFIG_SMP=n TIF_SPEC_IB is not
 		 * in the TIF_WORK_CTXSW masks.
 		 */