uncrustify.sh: modify to use distro uncrstify
uncrustify.sh: modify to use distro uncrstify

With debian buster, uncrustify from apt is recent enough to give valid
results.

Signed-off-by: Enrico Joerns <a2e5f936c390f36494e46e71bcfbe365bb1e8c49@pengutronix.de>

jluebbe/rauc,rauc/rauc,rauc/rauc,jluebbe/rauc,jluebbe/rauc,rauc/rauc,ejoerns/rauc,ejoerns/rauc,ejoerns/rauc