physmem: Rename addr1 to more informative mr_addr in flatview_read/write() and similar

physmem: Rename addr1 to more informative mr_addr in flatview_read/write() and similar

The calls to flatview_read/write[_continue]() have parameters addr and
addr1 but the names give no indication of what they are addresses of.
Rename addr1 to mr_addr to reflect that it is the translated address
offset within the MemoryRegion returned by flatview_translate().
Similarly rename the parameter in address_space_read/write_cached_slow()

Suggested-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20240307153710.30907-2-Jonathan.Cameron@huawei.com
Signed-off-by: Peter Xu <peterx@redhat.com>