staging: axis-fifo: use unique identifiers in device names

staging: axis-fifo: use unique identifiers in device names

Axis-fifo devices use physical addresses in their name, for example
'axis_fifo_0x43c00000'. This is generally frowned upon and it does not
follow the usual naming scheme that uses unique identifiers.

Therefore, use ida_alloc()/ida_free() to implement unique identifiers
for axis-fifo device names (i.e. axis_fifo0, axis_fifo1, etc.).

Signed-off-by: Ovidiu Panait <ovidiu.panait.oss@gmail.com>
Link: https://lore.kernel.org/r/20250811085417.2641674-2-ovidiu.panait.oss@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>