Revert "bcm21553-common: remove prebuilt rild & libril #2"

This reverts commit 6441739646964a06e1ebe10043d3b4d2c7b27875.
Revert "bcm21553-common: remove prebuilt rild & libril"

This reverts commit f9f4f48361be69b23cc0134e15e586b611591e45.