Delete unnecessary fix_db2_mac make target (Yelp#254)

Makefile

@@ -24,13 +24,3 @@ clean:
 super-clean: clean
 	rm -rf .tox
 	rm -rf venv
-
-.PHONY: fix-db2-mac
-fix-db2-mac:
-	# comment out lines for any interpreters that aren't installed on your machine
-	install_name_tool -change libdb2.dylib $(PROJECT_DIR)/.tox/py27/lib/python2.7/site-packages/clidriver/lib/libdb2.dylib $(PROJECT_DIR)/.tox/py27/lib/python2.7/site-packages/ibm_db.so
-	install_name_tool -change libbd2.dylib $(PROJECT_DIR)/.tox/py35/lib/python3.5/site-packages/clidriver/lib/libdb2.dylib $(PROJECT_DIR)/.tox/py35/lib/python3.5/site-packages/ibm_db.cpython-35m-darwin.so
-	install_name_tool -change libbd2.dylib $(PROJECT_DIR)/.tox/py36/lib/python3.6/site-packages/clidriver/lib/libdb2.dylib $(PROJECT_DIR)/.tox/py36/lib/python3.6/site-packages/ibm_db.cpython-36m-darwin.so
-	install_name_tool -change libdb2.dylib $(PROJECT_DIR)/.tox/py37/lib/python3.7/site-packages/clidriver/lib/libdb2.dylib $(PROJECT_DIR)/.tox/py37/lib/python3.7/site-packages/ibm_db.cpython-37m-darwin.so
-	install_name_tool -change libdb2.dylib $(PROJECT_DIR)/.tox/pypy/site-packages/clidriver/lib/libdb2.dylib $(PROJECT_DIR)/.tox/pypy/site-packages/ibm_db.pypy-41.so
-	install_name_tool -change libdb2.dylib $(PROJECT_DIR)/.tox/pypy3/site-packages/clidriver/lib/libdb2.dylib $(PROJECT_DIR)/.tox/pypy3/site-packages/ibm_db.pypy3-71-darwin.so