spi: bcm2835: Remove shared interrupt support

This reverts commit ecfbd3cf3b8b since Lukas Wunner noticed that we
start operating on the hardware before we check to see if this is a
spurious interrupt.

Reported-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
1 file changed