nativesdk-qtbase_git: re-add OEQt5Toolchain to SRC_URI

The file is expected by do_install(), but _git version resets SRC_URI.

Signed-off-by: Denys Dmytriyenko <denys@ti.com>
Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>
nativesdk-qtbase.inc: avoid removing directories, namely /usr/lib itself

Signed-off-by: Denys Dmytriyenko <denys@ti.com>
Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>