ARM: dts: ti/omap: gta04: fix pm issues caused by spi module

ARM: dts: ti/omap: gta04: fix pm issues caused by spi module

Despite CM_IDLEST1_CORE and CM_FCLKEN1_CORE behaving normal,
disabling SPI leads to messages like when suspending:
Powerdomain (core_pwrdm) didn't enter target state 0
and according to /sys/kernel/debug/pm_debug/count off state is not
entered. That was not connected to SPI during the discussion
of disabling SPI. See:
https://lore.kernel.org/linux-omap/20230122100852.32ae082c@aktux/

The reason is that SPI is per default in slave mode. Linux driver
will turn it to master per default. It slave mode, the powerdomain seems to
be kept active if active chip select input is sensed.

Fix that by explicitly disabling the SPI3 pins which used to be muxed by
the bootloader since they are available on an optionally fitted header
which would require dtb overlays anyways.

Fixes: a622310f7f01 ("ARM: dts: gta04: fix excess dma channel usage")
CC: stable@vger.kernel.org
Signed-off-by: Andreas Kemnade <andreas@kemnade.info>
Reviewed-by: Roger Quadros <rogerq@kernel.org>
Link: https://lore.kernel.org/r/20241204174152.2360431-1-andreas@kemnade.info
Signed-off-by: Kevin Hilman <khilman@baylibre.com>