Older MIPS chips have a QSPI/MSPI controller that does not have the
MSPI_REV offset, reading from that offset will cause a bus error. Match
their compatible string and do not perform a read from that register in
that case.
Signed-off-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
Signed-off-by: Kamal Dasu <kdasu.kdev@xxxxxxxxx>