habanalabs: support debugfs Byte access to device DRAM

The habanalabs HW requires memory resources to be used by its
internal hardware structures. These structures are allocated and
initialized by the driver. We would like to use the device HBM for
that purpose. This memory is io-remapped and accessed using the
writel()/writeb()/writew() commands.
Since some of the HW structures are one byte in size we need to
add support for the  writeb() and readb() functions in the driver.

Signed-off-by: Moti Haimovski <mhaimovski@habana.ai>
Reviewed-by: Oded Gabbay <ogabbay@kernel.org>
Signed-off-by: Oded Gabbay <ogabbay@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>