If upstream believes -ffast-math is ok for this part then that is
fine, but we do not want to override users' -O.
--- a/3rdparty/soundtouch/CMakeLists.txt
+++ b/3rdparty/soundtouch/CMakeLists.txt
@@ -43 +43 @@
-		target_compile_options(pcsx2-soundtouch PRIVATE -Ofast)
+		target_compile_options(pcsx2-soundtouch PRIVATE -ffast-math)