tools/xl: Allow compilation of 'xl resume' command on Arm

The "xl resume" command was previously excluded from Arm builds because
system suspend/resume (e.g., SYSTEM_SUSPEND via vPSCI) was not
implemented. On x86, this command is used for resume.

This change enables compilation of `xl resume` on Arm regardless of the
underlying implementation status, making the tool available for testing
and future feature support. The relevant libxl infrastructure and handler
functions are already present and usable.

Note: This does not imply full system suspend/resume support on Arm.
      The `xl suspend` command still does not work on Arm platforms.

Signed-off-by: Mykola Kvach <mykola_kvach@epam.com>
Acked-by: Anthony PERARD <anthony.perard@vates.tech>

tools/include/libxl.h

@@ -1145,7 +1145,6 @@ typedef struct libxl__ctx libxl_ctx;
  * restoring or migrating a domain. In this case the related functions
  * should be expected to return failure. That is:
  *  - libxl_domain_suspend
- *  - libxl_domain_resume
  *  - libxl_domain_remus_start
  */
 #if defined(__arm__) || defined(__aarch64__)

tools/xl/xl.h

@@ -65,7 +65,7 @@ static const char migrate_permission_to_go[]=
     "domain is yours, you are cleared to unpause";
 static const char migrate_report[]=
     "my copy unpause results are as follows";
-#endif
+#endif /* !LIBXL_HAVE_NO_SUSPEND_RESUME */
 
   /* followed by one byte:
    *     0: everything went well, domain is running
@@ -130,8 +130,8 @@ int main_migrate_receive(int argc, char **argv);
 int main_save(int argc, char **argv);
 int main_migrate(int argc, char **argv);
 int main_suspend(int argc, char **argv);
+#endif /* !LIBXL_HAVE_NO_SUSPEND_RESUME */
 int main_resume(int argc, char **argv);
-#endif
 int main_dump_core(int argc, char **argv);
 int main_pause(int argc, char **argv);
 int main_unpause(int argc, char **argv);

tools/xl/xl_cmdtable.c

@@ -198,12 +198,12 @@ const struct cmd_spec cmd_table[] = {
       "Suspend a domain to RAM",
       "<Domain>",
     },
+#endif /* !LIBXL_HAVE_NO_SUSPEND_RESUME */
     { "resume",
       &main_resume, 0, 1,
       "Resume a domain from RAM",
       "<Domain>",
     },
-#endif
     { "dump-core",
       &main_dump_core, 0, 1,
       "Core dump a domain",
@@ -548,7 +548,7 @@ const struct cmd_spec cmd_table[] = {
       "                        checkpoint must be disabled.\n"
       "-p                      Use COLO userspace proxy."
     },
-#endif
+#endif /* !LIBXL_HAVE_NO_SUSPEND_RESUME */
     { "devd",
       &main_devd, 0, 1,
       "Daemon that listens for devices and launches backends",

tools/xl/xl_migrate.c

@@ -767,7 +767,7 @@ int main_remus(int argc, char **argv)
     close(send_fd);
     return EXIT_FAILURE;
 }
-#endif
+#endif /* !LIBXL_HAVE_NO_SUSPEND_RESUME */
 
 
 /*

tools/xl/xl_saverestore.c

@@ -270,7 +270,7 @@ int main_save(int argc, char **argv)
     return EXIT_SUCCESS;
 }
 
-#endif /* LIBXL_HAVE_NO_SUSPEND_RESUME */
+#endif /* !LIBXL_HAVE_NO_SUSPEND_RESUME */
 
 
 

tools/xl/xl_vmcontrol.c

@@ -38,11 +38,6 @@ static void suspend_domain(uint32_t domid)
     libxl_domain_suspend_only(ctx, domid, NULL);
 }
 
-static void resume_domain(uint32_t domid)
-{
-    libxl_domain_resume(ctx, domid, 1, NULL);
-}
-
 int main_suspend(int argc, char **argv)
 {
     int opt;
@@ -55,6 +50,12 @@ int main_suspend(int argc, char **argv)
 
     return EXIT_SUCCESS;
 }
+#endif /* !LIBXL_HAVE_NO_SUSPEND_RESUME */
+
+static void resume_domain(uint32_t domid)
+{
+    libxl_domain_resume(ctx, domid, 1, NULL);
+}
 
 int main_resume(int argc, char **argv)
 {
@@ -68,7 +69,6 @@ int main_resume(int argc, char **argv)
 
     return EXIT_SUCCESS;
 }
-#endif
 
 static void pause_domain(uint32_t domid)
 {