package/ti-sgx-km: new package

package/ti-sgx-km: new package

This package adds the kernel module for the SGX graphics accelerator of the
following Texas Instuments SoCs: AM335x, AM437x, AM4430, AM5430

Signed-off-by: Lothar Felten <lothar.felten@gmail.com>
[Thomas:
 - Add Config.in comment about Linux kernel dependency
 - Extend Config.in help text to indicate that a TI specific kernel is
   needed
 - Fetch using git:// since fetching from http://, since fetching over
   http:// doesn't work.]
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>