spi: sh-msiof: avoid integer overflow in constants

spi: sh-msiof: avoid integer overflow in constants

cppcheck rightfully warned:

 drivers/spi/spi-sh-msiof.c:792:28: warning: Signed integer overflow for expression '7<<29'. [integerOverflow]
 sh_msiof_write(p, SIFCTR, SIFCTR_TFWM_1 | SIFCTR_RFWM_1);

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://msgid.link/r/20240130094053.10672-1-wsa+renesas@sang-engineering.com
Signed-off-by: Mark Brown <broonie@kernel.org>