Implement an update simulator to verify BB OTA packages on host

Implement the simulator runtime and build the updater simulator as a host
executable. The code to parse the target-files and mocks the block devices
will be submitted in the follow-up.

Bug: 131911365
Test: unit tests pass

Change-Id: Ib1ba939aec8333ca68a45139514d772ad7a27ad8
diff --git a/otautil/Android.bp b/otautil/Android.bp
index 73398c3..871dcae 100644
--- a/otautil/Android.bp
+++ b/otautil/Android.bp
@@ -24,12 +24,16 @@
 
     // Minimal set of files to support host build.
     srcs: [
+        "dirutil.cpp",
         "paths.cpp",
         "rangeset.cpp",
+        "sysutil.cpp",
     ],
 
     shared_libs: [
         "libbase",
+        "libcutils",
+        "libselinux",
     ],
 
     export_include_dirs: [
@@ -39,12 +43,10 @@
     target: {
         android: {
             srcs: [
-                "dirutil.cpp",
                 "logging.cpp",
                 "mounts.cpp",
                 "parse_install_logs.cpp",
                 "roots.cpp",
-                "sysutil.cpp",
                 "thermalutil.cpp",
             ],
 
@@ -57,10 +59,8 @@
             ],
 
             shared_libs: [
-                "libcutils",
                 "libext4_utils",
                 "libfs_mgr",
-                "libselinux",
             ],
 
             export_static_lib_headers: [