s390/mm,fault: remove not needed tsk variable

tsk is only used as an intermediate variable for current. Remove tsk
and use current directly instead at the only place where it is used.
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>

arch/s390/mm/fault.c

@@ -280,7 +280,6 @@ static void do_sigbus(struct pt_regs *regs)
 static void do_exception(struct pt_regs *regs, int access)
 {
 	struct vm_area_struct *vma;
-	struct task_struct *tsk;
 	unsigned long address;
 	struct mm_struct *mm;
 	enum fault_type type;
@@ -289,7 +288,6 @@ static void do_exception(struct pt_regs *regs, int access)
 	vm_fault_t fault;
 	bool is_write;
 
-	tsk = current;
 	/*
 	 * The instruction that caused the program check has
 	 * been nullified. Don't signal single step via SIGTRAP.
@@ -297,7 +295,7 @@ static void do_exception(struct pt_regs *regs, int access)
 	clear_thread_flag(TIF_PER_TRAP);
 	if (kprobe_page_fault(regs, 14))
 		return;
-	mm = tsk->mm;
+	mm = current->mm;
 	address = get_fault_address(regs);
 	is_write = fault_is_write(regs);
 	type = get_fault_type(regs);