tinyexr: Sync with upstream 1.0.1

Removes miniz as a bundled dependency, relies on our own zlib instead.

Includes a couple commits ahead of `v1.0.1` tag to fix MinGW builds.

thirdparty/tinyexr/tinyexr.cc

@@ -4,5 +4,9 @@
 #endif
 #endif
 
+// -- GODOT start --
+#include <zlib.h> // Should come before including tinyexr.
+// -- GODOT end --
+
 #define TINYEXR_IMPLEMENTATION
 #include "tinyexr.h"