scons: Add MinGW-w64 prefixes for MinGW build.
diff --git a/scons/crossmingw.py b/scons/crossmingw.py
index 8adc8f5..8af0d93 100644
--- a/scons/crossmingw.py
+++ b/scons/crossmingw.py
@@ -54,11 +54,13 @@
     i586-mingw32msvc-
     i686-mingw32msvc-
     i686-pc-mingw32-
+    i686-w64-mingw32-
 """)
 prefixes64 = SCons.Util.Split("""
     amd64-mingw32-
     amd64-mingw32msvc-
     amd64-pc-mingw32-
+    x86_64-w64-mingw32-
 """)
 
 def find(env):