nvmem: layouts: Add fixed-layout driver

nvmem: layouts: Add fixed-layout driver

Current implementation isn't working well when device tree nodes have a
phandle on a fixed-layout nvmem node. As the fixed layout is handled in
nvmem core, no driver is ever associated with the layout, and the device
consumer driver probe is deferred indefinitely.

Remove the specific handling of fixed-layout and add a layout driver.
This makes the fixed-layout similar to all other layouts, fixing the
whole issue.

Fixes: fc29fd821d9a ("nvmem: core: Rework layouts to become regular devices")
Cc: stable@vger.kernel.org
Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Mathieu Dubois-Briand <mathieu.dubois-briand@bootlin.com>
Signed-off-by: Srinivas Kandagatla <srini@kernel.org>
Link: https://patch.msgid.link/20260724223404.629248-3-srini@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>