frv: add io{read,write}{16,32}be functions

These functions are used in various drivers, including the latest
version of the 8250 driver. The latter causes the following build
failure.

drivers/tty/serial/8250/8250_core.c: In function 'mem32be_serial_out':
drivers/tty/serial/8250/8250_core.c:456:2: error:
			implicit declaration of function 'iowrite32be'
drivers/tty/serial/8250/8250_core.c: In function 'mem32be_serial_in':
drivers/tty/serial/8250/8250_core.c:462:2: error:
			implicit declaration of function 'ioread32be'

Cc: Kevin Cernekee <cernekee@gmail.com>
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fixes: c627f2ce ("serial: 8250: Add support for big-endian MMIO
	accesses")
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NRob Herring <robh@kernel.org>

arch/frv/include/asm/io.h

@@ -342,6 +342,11 @@ static inline void iowrite32(u32 val, void __iomem *p)
 		__flush_PCI_writes();
 }
 
+#define ioread16be(addr)	be16_to_cpu(ioread16(addr))
+#define ioread32be(addr)	be32_to_cpu(ioread32(addr))
+#define iowrite16be(v, addr)	iowrite16(cpu_to_be16(v), (addr))
+#define iowrite32be(v, addr)	iowrite32(cpu_to_be32(v), (addr))
+
 static inline void ioread8_rep(void __iomem *p, void *dst, unsigned long count)
 {
 	io_insb((unsigned long) p, dst, count);