Add two SDIO-related libraries
Added to Components files for all ROM builds that could, in theory, have WiFi drivers, and to Disc so that softloadable builds are possible.
This MR no longer relies upon !46 (merged) having been merged first, since it's the only outstanding dependency. Note however that the PineA64 Components file will need to have both SDIOLib and SMHCLib adding to it - this information cannot be reinstated by an automatic merge.
You will also need to merge Products/BCM2835!9 (merged), Products/Disc!11 (merged), Products/OMAP3!6 (merged), Products/OMAP4!6 (merged), Products/OMAP5!6 (merged) and Products/iMx6!5 (merged) first.