Please post your code (and Makefile) within CODE tags; that way, the text maintains its proper indentation.
As for the issue you are having, use PWD instead of pwd, and be careful with your hyphens (it would appear that the one you are using is not the proper format).
Here's what the Makefile should look like:
make -C /lib/modules/$(shell uname -r)/build M=$(PWD) modules
make -C /lib/modules/$(shell uname -r)/build M=$(PWD) clean