Use acpi_os_map_memory() instead of ioremap() in einj driver

ioremap() has become more picky and is now spitting out console messages like:

 ioremap error for 0xbddbd000-0xbddbe000, requested 0x10, got 0x0

when loading the einj driver.  What we are trying to so here is map
a couple of data structures that the EINJ table points to. Perhaps
acpi_os_map_memory() is a better tool for this?
Most importantly it works, but as a side benefit it maps the structures
into kernel virtual space so we can access them with normal C memory
dereferences, so instead of using:
	writel(param1, &v5param->apicid);
we can use the more natural:
	v5param->apicid = param1;

Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>