Add `etcpak` library for faster ETC/ETC2/S3TC imports.

- `etc` module was renamed to `etcpak` and modified to use the new library.
- PKM importer is removed in the process, it's obsolete.
- Old library `etc2comp` is removed.
- S3TC compression no longer done via `squish` (but decompression still is).
- Slight modifications to etcpak sources for MinGW compatibility,
  to fix LLVM `-Wc++11-narrowing` errors, and to allow using vendored or
  system libpng.

Co-authored-by: Rémi Verschelde <rverschelde@gmail.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/thirdparty/etcpak/Timing.hpp b/thirdparty/etcpak/Timing.hpp
new file mode 100644
index 0000000000..3767e20f24
--- /dev/null
+++ b/thirdparty/etcpak/Timing.hpp
@@ -0,0 +1,8 @@
+#ifndef __DARKRL__TIMING_HPP__
+#define __DARKRL__TIMING_HPP__
+
+#include <stdint.h>
+
+uint64_t GetTime();
+
+#endif