uml: remove init_irq_signals

init_irq_signals doesn't need to be called from the context of a new process.
It initializes handlers, which are useless in process context.  With that call
gone, init_irq_signals has only one caller, so it can be inlined into
init_new_thread_signals.
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/um/include/os.h

@@ -285,7 +285,6 @@ extern void os_free_irq_later(struct irq_fd *active_fds,
 extern int os_get_pollfd(int i);
 extern void os_set_pollfd(int i, int fd);
 extern void os_set_ioignore(void);
-extern void init_irq_signals(int on_sigstack);
 
 /* sigio.c */
 extern int add_sigio_fd(int fd);

arch/um/os-Linux/irq.c

@@ -136,14 +136,3 @@ void os_set_ioignore(void)
 {
 	signal(SIGIO, SIG_IGN);
 }
-
-void init_irq_signals(int on_sigstack)
-{
-	int flags;
-
-	flags = on_sigstack ? SA_ONSTACK : 0;
-
-	set_handler(SIGIO, (__sighandler_t) sig_handler, flags | SA_RESTART,
-		    SIGUSR1, SIGIO, SIGWINCH, SIGVTALRM, -1);
-	signal(SIGWINCH, SIG_IGN);
-}

arch/um/os-Linux/process.c

@@ -249,7 +249,10 @@ void init_new_thread_signals(void)
 		    SIGUSR1, SIGIO, SIGWINCH, SIGVTALRM, -1);
 	signal(SIGHUP, SIG_IGN);
 
-	init_irq_signals(1);
+	set_handler(SIGIO, (__sighandler_t) sig_handler,
+		    SA_ONSTACK | SA_RESTART, SIGUSR1, SIGIO, SIGWINCH, SIGALRM,
+		    SIGVTALRM, -1);
+	signal(SIGWINCH, SIG_IGN);
 }
 
 int run_kernel_thread(int (*fn)(void *), void *arg, jmp_buf **jmp_ptr)