microblaze: cache: introduce flush_dcache_range()

Align microblaze with the other architectures and provide an
implementation for flush_dcache_range(). Also, remove the microblaze
exception in drivers/core/device.c.

Signed-off-by: Ovidiu Panait <ovpanait@gmail.com>
Link: https://lore.kernel.org/r/20220531181435.3473549-11-ovpanait@gmail.com


Signed-off-by: Michal Simek <michal.simek@amd.com>