In commit
46d03d37bf3a75e86f9f8ab56c6a939d04f23383 I renamed a Makefile target
from md5 to checksums, (as we switched from MD5 checksums to SHA-256
checksums, so the more general name is more future proof).
But that commit missed one mention of "md5" as a dependency of the .PHONY
target. Rename that here as well.
@-sha256sum $(PACKAGE_NAME).tar.bz2
@-sha256sum $(PACKAGE_NAME).zip
-.PHONY: tarballs md5
+.PHONY: tarballs checksums