scripts: try to workaround mingw bug by adding sse2

scripts/build_mingw_engine.sh

@@ -6,8 +6,8 @@
 cd $TRAVIS_BUILD_DIR
 export CC="ccache i686-w64-mingw32-gcc"
 export CXX="ccache i686-w64-mingw32-g++"
-export CFLAGS="-static-libgcc -no-pthread"
-export CXXFLAGS="-static-libgcc -static-libstdc++ -no-pthread"
+export CFLAGS="-static-libgcc -no-pthread -msse2" # add sse2 to workaround mingw multiple definition of MemoryBarrier bug
+export CXXFLAGS="-static-libgcc -static-libstdc++ -no-pthread -msse2"
 export LDFLAGS="-static-libgcc -static-libstdc++ -no-pthread"
 export LINKFLAGS="-static-libgcc -static-libstdc++ -no-pthread"
 export WINRC="i686-w64-mingw32-windres"

wscript

@@ -30,7 +30,7 @@ SUBDIRS = [
 	Subproject('public',      dedicated=False),
 	Subproject('engine',      dedicated=False),
 	Subproject('game_launch', singlebin=True),
-        Subproject('ref_gl'),
+	Subproject('ref_gl'),
 	Subproject('mainui'),
 	Subproject('vgui_support'),
 ]
@@ -170,8 +170,8 @@ def configure(conf):
 
 
 	# indicate if we are packaging for Linux/BSD
-	if(not conf.options.WIN_INSTALL and 
-		conf.env.DEST_OS != 'win32' and 
+	if(not conf.options.WIN_INSTALL and
+		conf.env.DEST_OS != 'win32' and
 		conf.env.DEST_OS != 'darwin'):
 		conf.env.LIBDIR = conf.env.BINDIR = '${PREFIX}/lib/xash3d'
 	else: