Some cleanup, moved PS2 code to drivers folder in the shared sources.

targets/_any/SConscript

@@ -33,6 +33,10 @@ extern const unsigned {symbol}_SIZE;
     env.Command([f'{res}.s', f'{res}.hpp'.replace('src/', 'include/')], res, action = _generate_s)
 env.AddMethod(_resource, 'Resource')
 
+irs_sources = Split('''
+    src/drivers/pic.cpp
+    src/drivers/ps2.cpp
+''')
 any_target_sources = Split('''
     src/app/main.cpp
 
@@ -51,5 +55,6 @@ any_target_sources = Split('''
 env.Resource(env.File('src/os/resources/lat9-08.psf').abspath, 'LAT9_08')
 
 env.Append(KERNEL_SOURCES = [env.File(f) for f in any_target_sources])
+env.Append(KERNEL_ISR_SOURCES = [env.File(f) for f in irs_sources])
 
 Return('env')