spi: spi-fsl-lpspi: fsl_lpspi_set_cmd(): remove obfuscated and obsolete assignment...

spi: spi-fsl-lpspi: fsl_lpspi_set_cmd(): remove obfuscated and obsolete assignment of TCR_CPOL and SPI_CPHA

Commit 7ae4d097b752 ("spi: spi-fsl-lpspi: Handle clock polarity and phase")
enhances the driver with clock polarity and phase handling.

Among other things that commit in fsl_lpspi_set_cmd() explicitly set the
bits TCR_CPOL and TCR_CPHA bits in the TCR register depending on their
corresponding bits in the SPI mode (SPI_CPOL and SPI_CPHA), to configure
clock polarity and phase.

That change made the assignment of the lowest 2 bits of lpspi_config::mode
shifted by << 30 to the TCR register obsolete. The lowest 2 bits of struct
lpspi_config::mode (= SPI_CPOL and SPI_CPHA) match the corresponding bits
in the TCR register (TCR_CPOL and TCR_CPHA) if shifted.

Keep the better readable and maintainable version provided in commit
7ae4d097b752 ("spi: spi-fsl-lpspi: Handle clock polarity and phase") and
remove the obfuscated version.

Cc: Marek Vasut <marex@nabladev.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Link: https://patch.msgid.link/20260319-spi-fsl-lpspi-cleanups-v2-5-02b56c5d44a8@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>