This patch is to replace the fixed value with expression.
Keep .file section as fixed values as it might be changed. The remaining sections will hardly be modified. So the Index values are sequential. By using expression, we can avoid the fixed value changes in coming patches.
This is a follow-up of patch D97117.
This seems not right as for now symbol 0 is always for .file, we don't need to make this one as the base, otherwise there is no meaning at all for this change. Now with this change, when we add some aux entry for .file symbol, we need to update all the following symbol entries. Without the change, with the .text symbol base, we don't need to do any change to existing symbols.