Build wine-pthread on Darwin.

diff --git a/configure b/configure
index 4846875..e3083ff 100755
--- a/configure
+++ b/configure
@@ -14685,6 +14685,12 @@
     MAIN_BINARY="wine-glibc"
 
     ;;
+  darwin*)
+    WINE_BINARIES="wine-pthread"
+
+    MAIN_BINARY="wine-pthread"
+
+    ;;
   *)
     WINE_BINARIES="wine-kthread"