signal: Remove task parameter from force_sig

All of the remaining callers pass current into force_sig so
remove the task parameter to make this obvious and to make
misuse more difficult in the future.

This also makes it clear force_sig passes current into force_sig_info.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

arch/unicore32/kernel/signal.c

@@ -129,7 +129,7 @@ asmlinkage int __sys_rt_sigreturn(struct pt_regs *regs)
 	return regs->UCreg_00;
 
 badframe:
-	force_sig(SIGSEGV, current);
+	force_sig(SIGSEGV);
 	return 0;
 }