otautil: Factor out the utils that're private to recovery.

A number of utility functions are intended for serving recovery's own
use. Exposing them via libotautil (which is a static lib) would pass the
dependencies onto libotautil's users (e.g. recovery image, updater, host
simulator, device-specific recovery UI/updater extensions etc). This CL
finds a new home for the utils that are private to recovery.

Test: mmma bootable/recovery
Change-Id: I575e97ad099b85fe1c1c8c7c9458a5a43d4e11e1

install/install.cpp

@@ -51,11 +51,11 @@
 #include "install/wipe_data.h"
 #include "otautil/error_code.h"
 #include "otautil/paths.h"
-#include "otautil/roots.h"
 #include "otautil/sysutil.h"
-#include "otautil/thermalutil.h"
 #include "private/setup_commands.h"
 #include "recovery_ui/ui.h"
+#include "recovery_utils/roots.h"
+#include "recovery_utils/thermalutil.h"
 
 using namespace std::chrono_literals;