Spi driver configuration
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Following PCDs are available for configuration of spi driver:
gMarvellTokenSpaceGuid.PcdSpiClockFrequency
Frequency (in Hz) of SPI clock
gMarvellTokenSpaceGuid.PcdSpiMaxFrequency
Max SCLK line frequency (in Hz) (max transfer frequency)
gMarvellTokenSpaceGuid.PcdSpiDefaultMode
default SCLK mode (see SPI_MODE enum in file OpenPlatformPkg/Drivers/Spi/MvSpi.h)