i3c/master/mipi-i3c-hci: Specify HAS_IOMEM dependency

The MIPI i3c HCI driver makes use of IOMEM functions like
devm_platform_ioremap_resource(), which are only available if
CONFIG_HAS_IOMEM is defined.

This causes the driver to be enabled under make ARCH=um allyesconfig,
even though it won't build.

By adding a dependency on HAS_IOMEM, the driver will not be enabled on
architectures which don't support it.

Fixes: 9ad9a52c ("i3c/master: introduce the mipi-i3c-hci driver")
Signed-off-by: David Gow <davidgow@google.com>
Acked-by: Nicolas Pitre <npitre@baylibre.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210127040636.1535722-1-davidgow@google.com
(cherry picked from commit 9d909f1b)