Sort the preprocessor compatibility section.

Using the original numerical order made more sense before they were changed to
doesnt_exist.

BUG=404754

Change-Id: I2971eff7c6fbe7c5d340b103de71bbfa180f1f96
Reviewed-on: https://boringssl-review.googlesource.com/5232
Reviewed-by: Adam Langley <agl@google.com>
1 file changed