Kernel: Remove duplicate Processor::restore_in_critical

There is already Processor::restore_critical, which does exactly the
same thing.

Kernel/Arch/x86_64/Processor.cpp

@@ -1493,7 +1493,7 @@ extern "C" void context_first_init([[maybe_unused]] Thread* from_thread, [[maybe
 
     auto in_critical = to_thread->saved_critical();
     VERIFY(in_critical > 0);
-    Processor::restore_in_critical(in_critical);
+    Processor::restore_critical(in_critical);
 
     // Since we got here and don't have Scheduler::context_switch in the
     // call stack (because this is the first time we switched into this
@@ -1554,7 +1554,7 @@ extern "C" void enter_thread_context(Thread* from_thread, Thread* to_thread)
 
     auto in_critical = to_thread->saved_critical();
     VERIFY(in_critical > 0);
-    Processor::restore_in_critical(in_critical);
+    Processor::restore_critical(in_critical);
 
     if (has_xsave_avx_support)
         asm volatile("xrstor %0" ::"m"(to_thread->fpu_state()), "a"(static_cast<u32>(SIMD::StateComponent::AVX | SIMD::StateComponent::SSE | SIMD::StateComponent::X87)), "d"(0u));

Kernel/Arch/x86_64/Processor.h

@@ -318,11 +318,6 @@ public:
         return read_gs_ptr(__builtin_offsetof(Processor, m_in_irq));
     }
 
-    ALWAYS_INLINE static void restore_in_critical(u32 critical)
-    {
-        write_gs_ptr(__builtin_offsetof(Processor, m_in_critical), critical);
-    }
-
     ALWAYS_INLINE static void enter_critical()
     {
         write_gs_ptr(__builtin_offsetof(Processor, m_in_critical), in_critical() + 1);