Add Makefile for OpenBSD

Makefile

@@ -0,0 +1,29 @@
+.PHONY : clean
+
+CFLAGS =		-std=c99 -Iinclude -pedantic -Wall -Wextra
+LDFLAGS =		-fPIC -shared
+
+TARGET = 	libflint.so
+SRC !=		ls src/*.c
+OBJ =			$(SRC:./src/$.c=./obj/%.o)
+
+PREFIX =	$(DESTDIR)/usr/local
+LIBDIR =	$(PREFIX)/lib
+
+all: $(TARGET)
+
+$(TARGET): $(OBJ)
+	cc $(CFLAGS) $(LDFLAGS) -o $(TARGET) $(OBJ)
+
+./obj/%.o: ./src/%.c
+	cc $(CFLAGS) -c $< -o $@
+
+install: $(TARGET)
+	cp $(TARGET) $(LIBDIR)
+
+uninstall:
+	rm -f $(LIBDIR)/$(TARGET)
+
+clean:
+	rm -f $(TARGET)
+