Add explicit Result::ok() checks where needed

Test: m checkbuild continuous_instrumentation_tests continuous_instrumentation_tests_api_coverage continuous_native_tests device-tests platform_tests
Exempt-From-Owner-Approval: mechanical mass refactoring
Change-Id: I8d40b1e3cb5d2f76baf77b8a190df4366909f7b6
diff --git a/init/reboot.cpp b/init/reboot.cpp
index 49baf9e..4699eca 100644
--- a/init/reboot.cpp
+++ b/init/reboot.cpp
@@ -853,7 +853,7 @@
         sub_reason = "apex";
         return result;
     }
-    if (!SwitchToMountNamespaceIfNeeded(NS_BOOTSTRAP)) {
+    if (!SwitchToMountNamespaceIfNeeded(NS_BOOTSTRAP).ok()) {
         sub_reason = "ns_switch";
         return Error() << "Failed to switch to bootstrap namespace";
     }