MIPS: Adjust LibartImgDeviceBaseAddress() for CC GC.

The concurrent copying GC allocates large contiguous
space at low addresses. This moves the image(s) out
of the way to higher addresses.

Test: booted MIPS32R2 in QEMU
Test: booted MIPS64 (with 2nd arch MIPS32R2) in QEMU

Change-Id: I1c54e6142844ab1ad7820765ae313650e9ab8875
diff --git a/android/config.go b/android/config.go
index bc76f34..2361920 100644
--- a/android/config.go
+++ b/android/config.go
@@ -439,7 +439,7 @@
 	default:
 		return "0x70000000"
 	case Mips, Mips64:
-		return "0x30000000"
+		return "0x64000000"
 	}
 }