base: unify some irq_session headers

remove repos/base-*/include/irq_session headers and use only a unification
from   repos/base/include/irq_session

first step

Issue #1456

repos/base-nova/lib/mk/base.mk

@@ -10,6 +10,7 @@ SRC_CC += console/log_console.cc
 SRC_CC += cpu/cache.cc
 SRC_CC += env/env.cc env/context_area.cc env/reinitialize.cc
 SRC_CC += thread/thread_nova.cc
+SRC_CC += irq/platform.cc
 
 INC_DIR += $(BASE_DIR)/src/base/env
 

repos/base-nova/src/core/include/irq_session_component.h

@@ -67,7 +67,8 @@ namespace Genode {
 			 ** Irq session interface **
 			 ***************************/
 
-			void wait_for_irq();
+			void       wait_for_irq();
+			Irq_signal signal();
 	};
 }
 

repos/base-nova/src/core/irq_session_component.cc

@@ -203,3 +203,10 @@ Irq_session_component::Irq_session_component(Cap_session     *cap_session,
 
 
 Irq_session_component::~Irq_session_component() { }
+
+
+Irq_signal Irq_session_component::signal()
+{
+	PDBG("not implemented;");
+	return Irq_signal();
+}