mtd: spi-nor: winbond: Make sure w25q{01, 02}jv behave correctly

These chips are internally made of two/four dies with linear addressing
capabilities to make it transparent to the user that two/four dies were
used. There is one drawback however, the read status operation is racy
as the status bit only gives the active die status and not the status of
the other die. For commands affecting the two dies, it means if another
command is sent too fast after the first die has returned a valid
status (deviation can be up to 200us), the chip will get corrupted/in an
unstable state.

The solution adopted here is to iterate manually over all internal
dies (which takes about 30us per die) until all are ready. This approach
will always be faster than a blind delay which represents the maximum
deviation, while also being totally safe.

A flash-specific hook for the status register read had to be
implemented. Testing with the flash_speed benchmark in Linux shown no
difference with the existing performances (using the regular status read
core function).

As the presence of multiple dies is not filled in these chips SFDP
tables (the table containing the crucial information is optional), we
need to manually wire the hook.

This change is adapted from Linux.

Link: https://lore.kernel.org/all/20250110-winbond-6-12-rc1-nor-volatile-bit-v3-1-735363f8cc7d@bootlin.com/
Signed-off-by: Miquel Raynal <[email protected]>

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