Move make_recovery_path and sparse_img to modules.

These two tools are only used within build system, so not adding them
to otatools.zip.

Bug: 63866463
Test: TreeHugger
Test: Build a non-A/B target that calls make_recovery_patch.
Change-Id: Iaeddc98a2c4a27c6b49d91047500029e460db9e3
diff --git a/tools/releasetools/Android.bp b/tools/releasetools/Android.bp
index 0e2f3de..80c233b 100644
--- a/tools/releasetools/Android.bp
+++ b/tools/releasetools/Android.bp
@@ -115,6 +115,17 @@
 }
 
 python_binary_host {
+    name: "make_recovery_patch",
+    defaults: ["releasetools_binary_defaults"],
+    srcs: [
+        "make_recovery_patch.py",
+    ],
+    libs: [
+        "releasetools_common",
+    ],
+}
+
+python_binary_host {
     name: "merge_builds",
     defaults: ["releasetools_binary_defaults"],
     srcs: [
@@ -143,6 +154,16 @@
     ],
 }
 
+python_binary_host {
+    name: "sparse_img",
+    defaults: ["releasetools_binary_defaults"],
+    srcs: [
+        "rangelib.py",
+        "sparse_img.py",
+    ],
+    main: "sparse_img.py",
+}
+
 python_defaults {
     name: "releasetools_test_defaults",
     srcs: [