Revert "[MTD] Driver for AT26Fxxx dataflash devices"

Revert "[MTD] Driver for AT26Fxxx dataflash devices"

This reverts commit 024442bd54604dbdfe7b3955e0340c598ecb9d7a.

It's not needed given the other m25p80 patch (which now handles
at26 "dataflash" as well as most other standard SPI flash chips),
and requires a controller driver that won't be merged upstream
(supplanted by drivers/spi/atmel_spi.c) ... the submitter of
that at91_dataflash26.c driver concurred.

Requested by David Brownell <david-b@pacbell.net>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>