mtd: rawnand: vf610_nfc: use regular comments for functions

mtd: rawnand: vf610_nfc: use regular comments for functions

These comments are not quite in kernel-doc format and they don't need
to be, so just use "/*" comment markers for them. This prevents these
kernel-doc warnings:

drivers/mtd/nand/raw/vf610_nfc.c:210: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
 * Read accessor for internal SRAM buffer
drivers/mtd/nand/raw/vf610_nfc.c:245: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
 * Write accessor for internal SRAM buffer

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Stefan Agner <stefan@agner.ch>
Cc: Miquel Raynal <miquel.raynal@bootlin.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Vignesh Raghavendra <vigneshr@ti.com>
Cc: linux-mtd@lists.infradead.org
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20230113064004.24391-1-rdunlap@infradead.org