Found these leaks using AppVerifier on Windows.

Bug: b/176981107
Change-Id: I89cbfc02e6adf0ea2a54cf80501fbbb3d0867964
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/51748Reviewed-by: Alexis Hétu <sugoi@google.com>
Tested-by: Antonio Maiorano <amaiorano@google.com>
Commit-Queue: Antonio Maiorano <amaiorano@google.com>