Rework PCI ata and serial drivers, program according to the progif byte

kernel/pci/serial/serial.h

@@ -0,0 +1,14 @@
+#ifndef PCI_SERIAL_SERIAL_H_
+#define PCI_SERIAL_SERIAL_H_
+
+#include <stdint.h>
+#include <stddef.h>
+
+typedef struct {
+  uint16_t iobase;
+  int lockstate;
+} PciSerialDev;
+
+void pci_serial_init(void);
+
+#endif // PCI_SERIAL_SERIAL_H_