LoongArch: Adjust arch_do_signal_or_restart() to adapt generic entry

Commit 8ba62d37 ("task_work: Call tracehook_notify_signal from
get_signal on all architectures") adjust arch_do_signal_or_restart() for
all architectures. LoongArch hasn't been upstream yet at that time and
can be still built successfully without adjustment because this function
has a weak version with the correct prototype. It is obviously that we
should convert LoongArch to use new API, otherwise some signal handlings
will be lost.
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

arch/loongarch/kernel/signal.c

@@ -529,11 +529,11 @@ static void handle_signal(struct ksignal *ksig, struct pt_regs *regs)
 	signal_setup_done(ret, ksig, 0);
 }
 
-void arch_do_signal_or_restart(struct pt_regs *regs, bool has_signal)
+void arch_do_signal_or_restart(struct pt_regs *regs)
 {
 	struct ksignal ksig;
 
-	if (has_signal && get_signal(&ksig)) {
+	if (get_signal(&ksig)) {
 		/* Whee!  Actually deliver the signal.	*/
 		handle_signal(&ksig, regs);
 		return;