Have androidmk ignore all-makefiles-under

That's automatically implemented now by the finder

Bug: b/37748825
Test: m -j nothing # which runs unit tests
Change-Id: Ie17907733a744dc97cd24c90bed73b4731e878ad

androidmk/cmd/androidmk/androidmk.go

@@ -177,6 +177,9 @@ func convertFile(filename string, buffer *bytes.Buffer) (string, []error) {
 					makeModule(file, val)
 				case val == clear_vars:
 					resetModule(file)
+				case val == include_ignored:
+					// subdirs are already automatically included in Soong
+					continue
 				default:
 					file.errorf(x, "unsupported include")
 					continue