cc_fuzz: add "data" field

"data" field specifies data dependencies that will be installed in
fuzzer's output directory.

"data" behaves similar to "corpus", except "data" preserves directory
structure, e.g.

    data: ["foo/bar.txt"]

is installed into

    $OUT/data/fuzz/<arch>/<target>/data/foo/bar.txt

Test: build a fuzzer with data depenency, check data is installed
correctly
Change-Id: Ia1255026278435181b6d93f91f8f9ad39c96d07f

cc/androidmk.go

@@ -317,6 +317,11 @@ func (fuzz *fuzzBinary) AndroidMk(ctx AndroidMkContext, ret *android.AndroidMkDa
 			filepath.Dir(fuzz.corpusIntermediateDir.String())+":corpus/"+d.Base())
 	}
 
+	for _, d := range fuzz.data {
+		fuzzFiles = append(fuzzFiles,
+			filepath.Dir(fuzz.dataIntermediateDir.String())+":data/"+d.Rel())
+	}
+
 	if fuzz.dictionary != nil {
 		fuzzFiles = append(fuzzFiles,
 			filepath.Dir(fuzz.dictionary.String())+":"+fuzz.dictionary.Base())