Added rtapi_ioperm() declaration for hal_speaker

This fixes the following compiler warning:

hal/drivers/hal_speaker.c: In function ‘rtapi_app_main’:
hal/drivers/hal_speaker.c:164:9: warning: implicit declaration of function ‘ioperm’ [-Wimplicit-function-declaration]
  164 |     if (ioperm(SPEAKER_PORT, 1, 1) < 0) {
      |         ^~~~~~

Author: petterreinholdtsen

docs/man/man3/rtapi_io.3rtapi

@@ -39,6 +39,8 @@ unsigned void rtapi_inb(unsigned char value, unsigned short int port);
 unsigned void rtapi_inw(unsigned short value, unsigned short int port);
 .HP
 unsigned void rtapi_inl(unsigned int value, unsigned short int port);
+.HP
+int rtapi_ioperm(unsigned long from, unsigned long num, int turn_on);
 
 .SH DESCRIPTION
 In kernel space, each rtapi_xxx or RTAPI_XXX identifier is mapped to the
@@ -47,7 +49,8 @@ underlying kernel functionality, if available.
 In userspace, or in kernels where the underlying functionality is not provided
 by a kernel, generally another implementation--possibly with reduced
 functionality--is provided.  (For example, the userspace implementation for
-rtapi_device_register always succeeds)
+rtapi_device_register and the kernel space implementation of rtapi_ioperm always
+succeeds)
 .SH REALTIME CONSIDERATIONS
 Call from init/cleanup code and from realtime tasks.  These functions will
 cause illegal instruction exceptions in userspace components, as well as in

src/hal/drivers/hal_speaker.c

@@ -64,6 +64,7 @@
 #include "config.h"     /* environment flags */
 #include "rtapi.h"		/* RTAPI realtime OS API */
 #include "rtapi_app.h"		/* RTAPI realtime module decls */
+#include "rtapi_io.h"
 #include "hal.h"		/* HAL public API decls */
 
 /* If FASTIO is defined, uses outb() and inb() from <asm.io>,
@@ -161,7 +162,7 @@ int rtapi_app_main(void)
 
 #if !defined(RTAPI_RTAI)
     /* STEP 1.1: get access to port, only needed in uspace builds */
-    if (ioperm(SPEAKER_PORT, 1, 1) < 0) {
+    if (rtapi_ioperm(SPEAKER_PORT, 1, 1) < 0) {
 	rtapi_print_msg(RTAPI_MSG_ERR,
 	    "SPEAKER: ERROR: ioperm() failed\n");
 	hal_exit(comp_id);

src/rtapi/rtapi_io.h

@@ -32,13 +32,15 @@
 #define rtapi_outb outb
 #define rtapi_outw outw
 #define rtapi_outl outl
+#define rtapi_ioperm ioperm
 #else
 #define rtapi_inb(x) (0)
 #define rtapi_inw(x) (0)
 #define rtapi_inl(x) (0)
 #define rtapi_outb(x,y) ((void)0)
 #define rtapi_outw(x,y) ((void)0)
 #define rtapi_outl(x,y) ((void)0)
+#define rtapi_ioperm(x,y,z) ((void)0)
 #endif
 
 #endif