soc/mediatek/mt8188/spi: Fix out-of-bound array access for pad_funcs

The size of the inner array of the 2-dimensional array pad_funcs should
be 4 instead of SPI_BUS_NUMBER (6). This bug leads to two extra
gpio_set_mode() calls with unexpected GPIOs.

Inspecting spi.o, the data immediately after the .rodata.pad_funcs
section is .rodata.spi_ctrlr_bus_map, with the following data:

 00000428  00 00 00 00 00 00 00 00  00 00 00 00 05 00 00 00
 00000438  00 00 00 00 00 00 00 00  ...

This is equivalent to the following calls:

 gpio_set_mode(GPIO(GPIO05), 0);
 gpio_set_mode(GPIO(GPIO00), 0);

The second call is already included in the pad_funcs array, so the first
call is the only practical impact of this bug.

Change-Id: I9c44f09b3cdadbbf039b95efca7144f213672092
Signed-off-by: Yu-Ping Wu <yupingso@chromium.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/84950
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Yidi Lin <yidilin@google.com>
Reviewed-by: Hung-Te Lin <hungte@chromium.org>
Reviewed-by: Paul Menzel <paulepanter@mailbox.org>

0 files changed, 0 insertions, 0 deletions