Cleaned up a few things before updating SwiftShader's version
in Chromium's DEPS file:
- Added Windows Subzero fix
- Removed commented out sysroot related lines
- Fixed formatting using git
- Temporarily disabled Subzero compilation for now

Change-Id: Ib6ae75c20869522675d28086ab170f01fd730f93
Reviewed-on: https://swiftshader-review.googlesource.com/8709Tested-by: Alexis Hétu <sugoi@google.com>
Reviewed-by: Nicolas Capens <capn@google.com>