Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/mips/include/asm/stackframe.h b/arch/mips/include/asm/stackframe.h
index 2161357..4d6ad90 100644
--- a/arch/mips/include/asm/stackframe.h
+++ b/arch/mips/include/asm/stackframe.h
@@ -427,9 +427,10 @@
 #ifdef CONFIG_CPU_MIPSR6
 		eretnc
 #else
+		.set	push
 		.set	arch=r4000
 		eret
-		.set	mips0
+		.set	pop
 #endif
 		.endm