Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/mips/pnx833x/Platform b/arch/mips/pnx833x/Platform
index 794526c..2872606 100644
--- a/arch/mips/pnx833x/Platform
+++ b/arch/mips/pnx833x/Platform
@@ -1,5 +1,5 @@
 # NXP STB225
 platform-$(CONFIG_SOC_PNX833X)	+= pnx833x/
-cflags-$(CONFIG_SOC_PNX833X)	+= -Iarch/mips/include/asm/mach-pnx833x
+cflags-$(CONFIG_SOC_PNX833X)	+= -I$(srctree)/arch/mips/include/asm/mach-pnx833x
 load-$(CONFIG_NXP_STB220)	+= 0xffffffff80001000
 load-$(CONFIG_NXP_STB225)	+= 0xffffffff80001000