mtd: spi-nor: core: fix kernel-doc typo for spi_nor_manufacturer_init_params()

When spi_nor_manufacturer_init_params() was added, the kernel-doc for it
contained a typo: 'struct spi-nor' instead of 'struct spi_nor' -- fix it.

Fixes: ce0b6f3f ("mtd: spi-nor: Add default_init() hook to tweak flash parameters")
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>