ti-pru-sw-edma-library: first addition of PRU sw edma library

ti-pru-sw-edma-library: first addition of PRU sw edma library

* Add PRU sw edma library recipe for the omapl138 and am181x-evm machines

This recipe builds and stages the edma user space libraries for use by
the PRU sw. Because the edma APIs available by the kernel can only be
called by kernel drivers, similar user space APIs (provided through this
recipe) were needed. These libraries depend on a kernel module built by
the ti-pru-sw-edma-driver recipe.

Signed-off-by: Melissa Watkins <m-watkins@ti.com>
Signed-off-by: Chase Maupin <chase.maupin@ti.com>
Signed-off-by: Koen Kooi <k-kooi@ti.com>