spi: tools: Add macro definitions to fix build errors

Add SPI_TX_OCTAL and SPI_RX_OCTAL to fix the following build errors:

CC       spidev_test.o
spidev_test.c: In function ‘transfer’:
spidev_test.c:131:13: error: ‘SPI_TX_OCTAL’ undeclared (first use in this function)
  if (mode & SPI_TX_OCTAL)
             ^
spidev_test.c:131:13: note: each undeclared identifier is reported only once for each function it appears in
spidev_test.c:137:13: error: ‘SPI_RX_OCTAL’ undeclared (first use in this function)
  if (mode & SPI_RX_OCTAL)
             ^
spidev_test.c: In function ‘parse_opts’:
spidev_test.c:290:12: error: ‘SPI_TX_OCTAL’ undeclared (first use in this function)
    mode |= SPI_TX_OCTAL;
            ^
spidev_test.c:308:12: error: ‘SPI_RX_OCTAL’ undeclared (first use in this function)
    mode |= SPI_RX_OCTAL;
            ^
  LD       spidev_test-in.o
ld: cannot find spidev_test.o: No such file or directory

Additionally, maybe SPI_CS_WORD and SPI_3WIRE_HIZ will be used in the future,
so add them too.

Fixes: 896fa735

 ("spi: spidev_test: Add support for Octal mode data transfers")
Signed-off-by: Qing Zhang <zhangqing@loongson.cn>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/1591880212-13479-2-git-send-email-zhangqing@loongson.cn
Signed-off-by: Mark Brown <broonie@kernel.org>