Kernel: Use a const reference to RegisterState in IRQ handling

Author: https://github.com/supercomputer7
Commit: e880fe0765
Pull-request: https://github.com/SerenityOS/serenity/pull/1396
Reviewed-by: https://github.com/awesomekling
Reviewed-by: https://github.com/shannonbooth ✅

Kernel/Interrupts/SharedIRQHandler.cpp

@@ -84,7 +84,7 @@ SharedIRQHandler::~SharedIRQHandler()
     disable_interrupt_vector();
 }
 
-void SharedIRQHandler::handle_interrupt(RegisterState& regs)
+void SharedIRQHandler::handle_interrupt(const RegisterState& regs)
 {
     ASSERT_INTERRUPTS_DISABLED();
     increment_invoking_counter();