arch, sched/signal: Fix compilation with ENABLE_PARTIAL_SIGNALS=y

Correct build errors when CONFIG_ENABLE_ALL_SIGNALS is not defined

- sched makefiles: Move pending-signal helpers from the ENABLE_ALL_SIGNALS-only
  list to the !DISABLE_ALL_SIGNALS list so signal dispatch is available in
  PARTIAL builds sched: make SIG_PREALLOC_ACTIONS, SIG_ALLOC_ACTIONS and
  SIG_DEFAULT depend on ENABLE_ALL_SIGNALS
- sched: fix ifdefs around pending-signal queue access and signal-mask for
  PARTIAL/DISABLE modes
- arch: gate SYS_signal_handler / _return calls and SYSCALL_LOOKUP(signal)
  with ENABLE_ALL_SIGNALS

Signed-off-by: Jukka Laitinen <jukka.laitinen@tii.ae>

include/nuttx/sched.h

@@ -519,8 +519,10 @@ struct task_group_s
 
 #ifdef CONFIG_ENABLE_ALL_SIGNALS
   sq_queue_t tg_sigactionq;         /* List of actions for signals              */
-  sq_queue_t tg_sigpendingq;        /* List of pending signals                  */
 #endif /* CONFIG_ENABLE_ALL_SIGNALS */
+#ifndef CONFIG_DISABLE_ALL_SIGNALS
+  sq_queue_t tg_sigpendingq;        /* List of pending signals                  */
+#endif /* !CONFIG_DISABLE_ALL_SIGNALS */
 #ifdef CONFIG_SIG_DEFAULT
   sigset_t tg_sigdefault;           /* Set of signals set to the default action */
 #endif

include/sys/syscall_lookup.h

@@ -217,8 +217,10 @@ SYSCALL_LOOKUP(pwrite,                     4)
 #endif
   SYSCALL_LOOKUP(poll,                     3)
   SYSCALL_LOOKUP(select,                   5)
+#ifndef CONFIG_DISABLE_ALL_SIGNALS
   SYSCALL_LOOKUP(ppoll,                    4)
   SYSCALL_LOOKUP(pselect,                  6)
+#endif
 #ifdef CONFIG_EVENT_FD
   SYSCALL_LOOKUP(eventfd,                  2)
 #endif
@@ -397,7 +399,9 @@ SYSCALL_LOOKUP(settimeofday,               2)
 
 /* ANSI C signal handling */
 
+#ifdef CONFIG_ENABLE_ALL_SIGNALS
 SYSCALL_LOOKUP(signal,                     2)
+#endif
 
 #ifdef CONFIG_SCHED_INSTRUMENTATION_DUMP
   SYSCALL_LOOKUP(sched_note_vprintf_ip,    5)