CONFIG_ETRAX_SPI_SSER1 is not available for thedefaultarchitecture x86.
Result is shown for architecture cris

SPI using synchronous serial port 1 (sser1)

configname: CONFIG_ETRAX_SPI_SSER1

Linux Kernel Configuration
└─>SPI using synchronous serial port 1 (sser1)
In linux kernel since version 2.6.25 (release Date: 2008-04-16)  
Say Y for an MMC/SD socket connected to synchronous serial port 1,
or for devices using the SPI protocol on that port. Say m if you
want to build it as a module, which will be named spi_crisv32_sser.
(You need to select MMC separately.)