Clean up userspace-reboot

The feature was deprecated last year.

Bug: 292469129
Test: atest CtsInitTestCases
Change-Id: I826502770ab3fa566be57a33829f1103efa893fb
diff --git a/init/property_service.cpp b/init/property_service.cpp
index 0d6eb15..053239f 100644
--- a/init/property_service.cpp
+++ b/init/property_service.cpp
@@ -102,7 +102,6 @@
 using android::properties::ParsePropertyInfoFile;
 using android::properties::PropertyInfoAreaFile;
 using android::properties::PropertyInfoEntry;
-using android::sysprop::InitProperties::is_userspace_reboot_supported;
 
 namespace android {
 namespace init {
@@ -569,8 +568,8 @@
         }
         LOG(INFO) << "Received sys.powerctl='" << value << "' from pid: " << cr.pid
                   << process_log_string;
-        if (value == "reboot,userspace" && !is_userspace_reboot_supported().value_or(false)) {
-            *error = "Userspace reboot is not supported by this device";
+        if (value == "reboot,userspace") {
+            *error = "Userspace reboot is deprecated.";
             return {PROP_ERROR_INVALID_VALUE};
         }
     }