i2c: at91: remove old polling driver

It will get replaced by a superior one. Safe to remove since this one
depends on BROKEN anyhow.

Signed-off-by: Nikolaus Voss <n.voss@weinmann.de>
Tested-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Reviewed-by: Nicolas Ferre <nicolas.ferre@atmel.com>

[wsa: added commit message]

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>