mtd: st_spi_fsm: Add support for Macronix MX25L3255E

This patch adds support for the Macronix MX25L3255E device.  Unlike the other
Macronix devices we have seen, this device supports WRITE_1_4_4 at reasonable
frequencies.  Rather than masking out WRITE_1_4_4 support altogether, we now
rely on the table parameters to indicate whether or not WRITE_1_4_4 should be
used.

Signed-off-by: Angus Clark <angus.clark@st.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>