Staging: cxt1e1: Replacing asm/io.h with linux/io.h

This patch fixes the warning "Use #include <linux/io.h> instead of
<asm/io.h>" generated by using checkpatch.pi.

Signed-off-by: Dulshani Gunawardhana <dulshani.gunawardhana89@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>