mtd: spi-nor: winbond: Add support for w25q64jwm

Add support Winbond w25q{64,128,256}jwm which are identical to existing
w25q32jwm except for their sizes.

This was tested with w25q64jwm, basic erase/write/readback and
lock/unlock both lower/upper blocks were okay.

Signed-off-by: ikjn@chromium.org <ikjn@chromium.org>
Signed-off-by: Xingyu Wu <wuxy@bitland.corp-partner.google.com>
Signed-off-by: ST Lin <stlin2@winbond.com>
Tested-by: Nicolas Boichat <drinkcat@chromium.org>

Signed-off-by: Ikjoon Jang <ikjn@chromium.org>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/20200928060631.2090541-1-ikjn@chromium.org