Kernel: Make Space::create API OOM safe

Author: https://github.com/bgianfo
Commit: https://github.com/SerenityOS/serenity/commit/8fc6168f21c
Pull-request: https://github.com/SerenityOS/serenity/pull/7520
Reviewed-by: https://github.com/supercomputer7

Kernel/VM/Space.cpp

@@ -20,7 +20,9 @@ OwnPtr<Space> Space::create(Process& process, const Space* parent)
     auto page_directory = PageDirectory::create_for_userspace(parent ? &parent->page_directory().range_allocator() : nullptr);
     if (!page_directory)
         return {};
-    auto space = adopt_own(*new Space(process, page_directory.release_nonnull()));
+    auto space = adopt_own_if_nonnull(new Space(process, page_directory.release_nonnull()));
+    if (!space)
+        return {};
     space->page_directory().set_space({}, *space);
     return space;
 }