spi: omap2-mcspi: Revert multi mode support

spi: omap2-mcspi: Revert multi mode support

There have been multiple reports that the multi-mode support in the
OMAP2 McSPI driver has caused regressions on existing systems.  There's
been some discussion and some proposed changes but nothing that's been
tested by all the reporters.  Drop the patch for v6.10, hopefully we can
get to the bottom of the issue and reenable the feature for v6.11.

Reported-by: Colin Foster <colin.foster@in-advantage.com>
Reported-by: João Paulo Gonçalves <jpaulo.silvagoncalves@gmail.com>
Fixes: e64d3b6fc9a3 ("spi: omap2-mcpsi: Enable MULTI-mode in more situations")
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://patch.msgid.link/20240704-spi-revert-omap2-multi-v1-1-69357ef13fdc@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>