[module.import] Clarify interface dependency definition

Author: opensdh

source/modules.tex

@@ -554,8 +554,8 @@
 
 \pnum
 A translation unit has an \defn{interface dependency} on a translation unit \tcode{U}
-if it contains a \grammarterm{module-declaration} or
-\grammarterm{module-import-declaration} that imports \tcode{U} or if it has
+if it contains a declaration (possibly a \grammarterm{module-declaration})
+that imports \tcode{U} or if it has
 an interface dependency on a translation unit that has an interface dependency on \tcode{U}.
 A translation unit shall not have an interface dependency on itself.
 \begin{example}