Kernel: Rename ScopedSpinlock => SpinlockLocker

This matches MutexLocker, and doesn't sound like it's a lock itself.

Kernel/FileSystem/SysFSComponent.cpp

@@ -14,7 +14,7 @@ static InodeIndex s_next_inode_index { 0 };
 
 static size_t allocate_inode_index()
 {
-    ScopedSpinlock lock(s_index_lock);
+    SpinlockLocker lock(s_index_lock);
     s_next_inode_index = s_next_inode_index.value() + 1;
     VERIFY(s_next_inode_index > 0);
     return s_next_inode_index.value();