Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/sh/include/asm/io.h b/arch/sh/include/asm/io.h
index 98cb8c8..ac05619 100644
--- a/arch/sh/include/asm/io.h
+++ b/arch/sh/include/asm/io.h
@@ -24,6 +24,7 @@
 #define __IO_PREFIX     generic
 #include <asm/io_generic.h>
 #include <asm/io_trapped.h>
+#include <asm-generic/pci_iomap.h>
 #include <mach/mangle-port.h>
 
 #define __raw_writeb(v,a)	(__chk_io_ptr(a), *(volatile u8  __force *)(a) = (v))
@@ -228,9 +229,6 @@
 
 #define IO_SPACE_LIMIT 0xffffffff
 
-/* synco on SH-4A, otherwise a nop */
-#define mmiowb()		wmb()
-
 /* We really want to try and get these to memcpy etc */
 void memcpy_fromio(void *, const volatile void __iomem *, unsigned long);
 void memcpy_toio(volatile void __iomem *, const void *, unsigned long);
@@ -371,7 +369,11 @@
 
 #define ioremap_nocache	ioremap
 #define ioremap_uc	ioremap
-#define iounmap		__iounmap
+
+static inline void iounmap(void __iomem *addr)
+{
+	__iounmap(addr);
+}
 
 /*
  * Convert a physical pointer to a virtual kernel pointer for /dev/mem