mtd: nand: raw: Use macro nand_to_mtd() where appropriate

In every other place in this file the macro is used, make it consistent.

Link: https://lore.kernel.org/all/20240320090214.40465-2-ada@thorsis.com


Fixes: 9d1806fa ("mtd: nand: Get rid of mtd variable in function calls")
Signed-off-by: Alexander Dahl <ada@thorsis.com>
Reviewed-by: Michael Trimarchi <michael@amarulasolutions.com>
Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>