m68k: Double cast io functions to unsigned long

m68k: Double cast io functions to unsigned long

m68k builds fail widely with errors such as

arch/m68k/include/asm/raw_io.h:20:19: error:
	cast to pointer from integer of different size
arch/m68k/include/asm/raw_io.h:30:32: error:
	cast to pointer from integer of different size [-Werror=int-to-p

On m68k, io functions are defined as macros. The problem is seen if the
macro parameter variable size differs from the size of a pointer. Cast
the parameter of all io macros to unsigned long before casting it to
a pointer to fix the problem.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20210907060729.2391992-1-linux@roeck-us.net
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>