Input: ads7846 - ratelimit the spi_sync error message

In case the touch controller is not connected, this message keeps scrolling
on the console indefinitelly. Ratelimit it to avoid filling kernel logs.

"
ads7846 spi2.1: spi_sync --> -22
"

Signed-off-by: Marek Vasut <marex@denx.de>
Link: https://lore.kernel.org/r/20240708211913.171243-1-marex@denx.de


Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>