linux-ti-staging_3.14: make kernel origin configurable
linux-ti-staging_3.14: make kernel origin configurable

Using variables for KERNEL_GIT_URI and KERNEL_GIT_PROTOCOL allows layer
bbappends to specify local repositories to test of pending changes that
are not available in the official TI kernel, without requiring
duplication of config fragments specified in SRC_URI in the base recipe.

Signed-off-by: Peter A. Bigot <650538893330be855f76604594b4820eb226769e@pabigot.com>
Signed-off-by: Denys Dmytriyenko <d29de71aea38aad3a87d486929cb0aad173ae612@ti.com>

joelagnel/meta-ti,smoosvi/Test4,rcn-ee/meta-ti,rcn-ee/meta-ti,RedFIR/meta-ti,smoosvi/Test4,joelagnel/meta-ti,tylerwhall/meta-ti,RedFIR/meta-ti,joelagnel/meta-ti,joelagnel/meta-ti,RedFIR/meta-ti,rcn-ee/meta-ti,rcn-ee/meta-ti,tylerwhall/meta-ti,tylerwhall/meta-ti,RedFIR/meta-ti,tylerwhall/meta-ti