clkconf: move clkconf from libgpio to it's own lib

Clock configuration will be needed by other/future subsystems such as i2c.
Extract the functionality from libgpio and put it into it's own library.

Change-Id: I6f6de0b3fb4d305ddfeac74123b78c983d1318dd
LLVM bitcode for almost the whole source tree

Change-Id: Ibc6f89de112e0649c3a3bfe49c2baa2ed0746212