davinci: Move IO device mapping macros from io.h to hardware.h

This patch takes out IO mapping macros from mach/io.h and puts them in
mach/hardware.h avoiding need to include mach/io.h in various files such as
serial.h, vmalloc.h etc.

The main reason to avoid inclusion of mach/io.h is, when default in/out macros
are overridden by machine specific functions (e.g., in case of PCI I/O), they
result into linker error. An example snippet and error snapshot is listed below.

Following code in mach/io.h:

	#define inl(p)  my_inl()

	static inline unsigned int my_inl(unsigned int addr)
	{
		if (IS_PCI_IO(addr))
			return pci_inl ();
		else
			return le32_to_cpu(__raw_readl(__typesafe_io(addr)));
	}

leads to error:
	LD      arch/arm/boot/compressed/vmlinux
	arch/arm/boot/compressed/misc.o: In function `my_inl':
	misc.c:(.text+0x2744): undefined reference to `pci_inl'
	make[2]: *** [arch/arm/boot/compressed/vmlinux] Error 1

This is because mach/io.h gets included in arch/arm/boot/compressed/misc.c
through mach/serial.h but pci.c file, which defines 'pci_inl' doesn't get built
into compressed vmlinux.

Signed-off-by: Hemant Pedanekar <hemantp@ti.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>