Working PIT irqs, fix GDT bugs

kernel/platform/i386_pc/sys/pic.h

@@ -32,6 +32,11 @@ SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #ifndef _SYS_PIC_H
 #define _SYS_PIC_H
 
+#include <libk/types.h>
+
 void pic_init(void);
+void pic_mask(void);
+void pic_unmask(void);
+void pic_fini(uint8_t trap);
 
 #endif // _SYS_PIC_H