make clean
make -C /usr/linux-headers-uname -r M=pwd V=1 clean
make[1]: Entering directory '/usr/src/linux-headers-4.4.38-v7+'
make[1]: ***No rule to make target 'clean'. Stop.
make[1]: Leaving directory '/usr/src/linux-headers-4.4.38-v7+'
Makefile:10: recipe for target 'clean' failed
make: *** [clean] Error 2