drivers: mipi_dbi: mipi_dbi_spi: change reset pin polarity

Change reset pin polarity for MIPI DBI SPI controller, so that the board
devicetree is responsible for setting the GPIO to active low, and the
driver always sets the pin to a logic 1 to reset the display.

Fixes #68562

Signed-off-by: Daniel DeGrasse <daniel.degrasse@nxp.com>