HPS eMMC Boot

Note: This example is not availble in this release. Refer to https://altera-fpga.github.io/rel-24.3/embedded-designs/stratix-10/sx/soc/emmc/ug-emmc-s10sx-soc/ for the latest available version. Also refer to https://altera-fpga.github.io/rel-26.1/embedded-designs/stratix-10/sx/soc/gsrd/ug-gsrd-s10sx-soc/ for the latest HPS Baseline System Example Design which now supports booting from eMMC.