Remove our .bbappend, which was wrongly making this recipe compatible with the
imx8. Directly port NXP's recipe (v5.4.39), which is newer than the one in
meta-freescale (v5.4.38).
https://jira.digi.com/browse/DEL-6722
Signed-off-by: Gabriel Valcazar <gabriel.valcazar@digi.com>