Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/powerpc/kernel/vector.S b/arch/powerpc/kernel/vector.S
index 21165da..8eb867d 100644
--- a/arch/powerpc/kernel/vector.S
+++ b/arch/powerpc/kernel/vector.S
@@ -21,6 +21,7 @@
 	REST_32VRS(0,r4,r3)
 	blr
 EXPORT_SYMBOL(load_vr_state)
+_ASM_NOKPROBE_SYMBOL(load_vr_state); /* used by restore_math */
 
 /*
  * Store VMX state into memory, including VSCR.