iProc chips have QSPI controller that does not have the MSPI_REV
offset. Reading from that offset will cause a bus error. Fix it by
having MSPI_REV query disabled in the generic compatible string.
Fixes: 3a01f04d74ef ("spi: bcm-qspi: Handle lack of MSPI_REV offset")
Link: https://lore.kernel.org/linux-arm-kernel/20200909211857.4144718-1-f.fainelli@xxxxxxxxx/T/#u
Signed-off-by: Ray Jui <ray.jui@xxxxxxxxxxxx>