[nap] Formalise the CPU sleeping API

src/core/console.c

@@ -1,11 +1,10 @@
 #include "stddef.h"
 #include "console.h"
 #include <gpxe/process.h>
+#include <gpxe/nap.h>
 
 /** @file */
 
-#include "bios.h"
-
 static struct console_driver console_drivers[0]
 	__table_start ( struct console_driver, console );
 static struct console_driver console_drivers_end[0]
@@ -82,9 +81,6 @@ static struct console_driver * has_input ( void ) {
  *
  * The character read will not be echoed back to any console.
  *
- * @bug We need a cleaner way to pick up cpu_nap().  It makes a
- * real-mode call, and so we don't want to use it with LinuxBIOS.
- *
  */
 int getchar ( void ) {
 	struct console_driver *console;

src/core/gdbudp.c

@@ -19,7 +19,6 @@
 #include <stdio.h>
 #include <string.h>
 #include <byteswap.h>
-#include <bios.h>
 #include <gpxe/iobuf.h>
 #include <gpxe/in.h>
 #include <gpxe/if_arp.h>
@@ -27,6 +26,7 @@
 #include <gpxe/ip.h>
 #include <gpxe/udp.h>
 #include <gpxe/netdevice.h>
+#include <gpxe/nap.h>
 #include <gpxe/gdbstub.h>
 #include <gpxe/gdbudp.h>
 

src/core/null_nap.c

@@ -0,0 +1,3 @@
+#include <gpxe/nap.h>
+
+PROVIDE_NAP_INLINE ( null, cpu_nap );