[PL] Change semantics of CLI parameter -Xpartial-linkage

This parameter accepts the name of the "mode" in which the partial linkage would work. Currently, only two options are supported: 'enable', 'disable'. But the list may be extended in the future as needed.

At the moment the 'disable' option is the default one. This will be changed in #KT-51447, #KT-51443.

compiler/testData/cli/js/jsExtraHelp.out

@@ -40,9 +40,10 @@ where advanced options include:
   -Xir-safe-external-boolean-diagnostic={log|exception}
                              Enable runtime diagnostics when access safely to boolean in external declarations
   -Xmetadata-only            Generate *.meta.js and *.kjsm files only
-  -Xpartial-linkage          Enable partial linkage mode
   -Xpartial-linkage-loglevel={info|warning|error}
                              Partial linkage compile-time log level
+  -Xpartial-linkage={enable|disable}
+                             Use partial linkage mode
   -Xstrict-implicit-export-types Generate strict types for implicitly exported entities inside d.ts files. Available in IR backend only.
   -Xtyped-arrays             Translate primitive arrays to JS typed arrays
   -Xes-classes               Generated JavaScript will use ES2015 classes.