Fix cycle printing

The patch "Fix panic when dependency cycle includes the first
module visited" caused cycles to print incorrectly by initializing
the current module to be the last module in the cycle, when it
should be the first module in the cycle.

Change-Id: Iaf939283a48faa4cc6eeb9b19aed57993575a687

context.go

@@ -1177,7 +1177,7 @@ func (c *Context) updateDependencies() (errs []error) {
 		})
 
 		// Iterate backwards through the cycle list.
-		curModule := cycle[len(cycle)-1]
+		curModule := cycle[0]
 		for i := len(cycle) - 1; i >= 0; i-- {
 			nextModule := cycle[i]
 			errs = append(errs, &Error{