data: Fix handling of vardepvalueexclude

The value used for exclusion was always being expanded. This is actually a bad idea since in most cases you'd want to exclude an unexpanded value and makes it impossible to use the variable as intended.

This adjusts things so the value is not expanded and we can correctly remove things from checksums much more easily.

index 60b2033..5872aee 100644
@@ -339,7 +339,7 @@ def build_dependencies(key, keys, shelldeps, varflagsexcl, d):

             deps |= parser.references
             deps = deps | (keys & parser.execs)
             return deps, value
-        varflags = d.getVarFlags(key, ["vardeps", "vardepvalue", "vardepsexclude", "vardepvalueexclude", "exports", "postfuncs", "prefuncs", "lineno", "filename"]) or {} +        varflags = d.getVarFlags(key, ["vardeps", "vardepvalue", "vardepsexclude", "exports", "postfuncs", "prefuncs", "lineno", "filename"]) or {} vardeps = varflags.get("vardeps")
         value = d.getVar(key, False)