update PhysFS to 3.2.0.

Fixes #1880.

src/modules/filesystem/physfs/Filesystem.cpp

@@ -123,6 +123,13 @@ const char *Filesystem::getName() const
 
 void Filesystem::init(const char *arg0)
 {
+#ifdef LOVE_ANDROID
+	// TODO: This should be a pointer to an initializeed PHYSFS_AndroidInit
+	// struct on android. But it's only used for PHYSFS_getBaseDir and
+	// PHYSFS_getPrefDir, which we don't use right now...
+	arg0 = nullptr;
+#endif
+
 	if (!PHYSFS_init(arg0))
 		throw love::Exception("Failed to initialize filesystem: %s", PHYSFS_getErrorByCode(PHYSFS_getLastErrorCode()));