Fix fopenmp issue in lib/Makefile
Fix fopenmp issue in lib/Makefile

souravsingh/khmer,ged-lab/khmer,F1000Research/khmer,jas14/khmer,ged-lab/khmer,jas14/khmer,souravsingh/khmer,ged-lab/khmer,kdmurray91/khmer,Winterflower/khmer,Winterflower/khmer,kdmurray91/khmer,souravsingh/khmer,kdmurray91/khmer,jas14/khmer,Winterflower/khmer,F1000Research/khmer,F1000Research/khmer