Factor out TI common Makefile components, no functional changes made, except
removing -f from the common Makefile for directory removal and adding -p
to directory creation.

Signed-off-by: Andrew F. Davis <afd@ti.com>
Reviewed-by: Igor Opaniuk <igor.opaniuk@linaro.org>

The default name for our kernel/dtb/OP-TEE FIT image has changed
from fitImage.itb to fitImage. Update this here.

Signed-off-by: Andrew F. Davis <afd@ti.com>
Reviewed-by: Joakim Bech <joakim.bech@linaro.org>

Signed-off-by: Andrew F. Davis <afd@ti.com>
Reviewed-by: Joakim Bech <joakim.bech@linaro.org>
[Rebase on top of master]
Signed-off-by: Jerome Forissier <jerome.forissier@linaro.org>