conf: am43: avoid missing dtb files for linux-ti-mainline
conf: am43: avoid missing dtb files for linux-ti-mainline

Avoid the inclusion of device tree files that do not exist upstream
when virtual/kernel is linux-ti-mainline for the am43xx machines.

Signed-off-by: Drew Fustini <880a0e8f2e6c168504ad0468c0b944e5371fb289@baylibre.com>
Signed-off-by: Denys Dmytriyenko <d29de71aea38aad3a87d486929cb0aad173ae612@konsulko.com>
Signed-off-by: Ryan Eatmon <c832a3efa8dfb59911a35349a6eeba0397feadf1@ti.com>

rcn-ee/meta-ti,rcn-ee/meta-ti,rcn-ee/meta-ti,rcn-ee/meta-ti