manifest: explicitly define the AOSP remote

Change-Id: I2c0aeb2d4951c6d71ee0f8c05925fb8fccef4ea5

default.xml

@@ -1,14 +1,15 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <manifest>
 
-  <remote  name="aosp"
-           fetch=".." />
+  <remote name="aosp"
+           fetch="https://android.googlesource.com"
+           review="android-review.googlesource.com" />
 
   <remote  name="github"
            fetch="https://github.com/" />
 
   <remote  name="omnirom"
-           fetch="https://github.com/omnirom" 
+           fetch="https://github.com/omnirom"
            review="gerrit.omnirom.org" />
 
   <default revision="refs/tags/android-7.0.0_r1"