sh: bring syscall_set_return_value in line with other architectures

Other architectures expect that syscall_set_return_value gets an already
negative value as error. That's also what kernel/seccomp.c provides.
Signed-off-by: Michael Karcher <kernel@mkarcher.dialup.fu-berlin.de>
Tested-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Signed-off-by: Rich Felker <dalias@libc.org>

arch/sh/include/asm/syscall_32.h

@@ -40,10 +40,7 @@ static inline void syscall_set_return_value(struct task_struct *task,
 					    struct pt_regs *regs,
 					    int error, long val)
 {
-	if (error)
-		regs->regs[0] = -error;
-	else
-		regs->regs[0] = val;
+	regs->regs[0] = (long) error ?: val;
 }
 
 static inline void syscall_get_arguments(struct task_struct *task,