updated makefile for windows build to copy the dll to builddir

Makefile

@@ -7,14 +7,12 @@ target = linux
 
 ifeq ($(target), windows)
 	CC = x86_64-w64-mingw32-gcc
-	CXX = x86_64-w64-mingw32-g++
 	EXT = .exe
 
 	CFLAGS = -Wall -o2 -I$(SRCDIR) -I$(VENDORDIR)/mariadb/include -I$(VENDORDIR)/duckdb/windows/include
 	LIBS = -L$(VENDORDIR)/mariadb/lib -llibmariadb -L$(VENDORDIR)/duckdb/windows/lib -lduckdb
 else
 	CC = gcc
-	CXX = g++
 	EXT =
 	CFLAGS = -Wall -O2 -I$(SRCDIR) `pkg-config --cflags libmariadb` -I$(VENDORDIR)/duckdb/linux/include
 	LIBS = `pkg-config --libs libmariadb` -L$(VENDORDIR)/duckdb/linux/lib -lduckdb
@@ -29,6 +27,7 @@ $(BUILDDIR)/$(APPNAME)$(EXT): $(OBJ)
 	@echo "Linking $@"
 	@mkdir -p $(dir $@)
 	$(CC) $(OBJ) -o $@ $(LIBS)
+	@cp vendor/duckdb/windows/lib/duckdb.dll $(BUILDDIR)
 
 $(BUILDDIR)/%.o: $(SRCDIR)/%.c
 	@echo "Compiling $<"