s390: remove pointless load within __switch_to

Remove a leftover from the code that transferred a couple of TIF bits
from the previous task to the next task.

Signed-off-by: Heiko Carstens <[e-mail]>
Signed-off-by: Martin Schwidefsky <[e-mail]>

arch/s390/kernel/entry.S

···
 	stmg	%r6,%r15,__SF_GPRS(%r15)	# store gprs of prev task
 	lgr	%r1,%r2
 	aghi	%r1,__TASK_thread		# thread_struct of prev task
-	lg	%r4,__TASK_thread_info(%r2)	# get thread_info of prev
 	lg	%r5,__TASK_thread_info(%r3)	# get thread_info of next
 	stg	%r15,__THREAD_ksp(%r1)		# store kernel stack of prev
 	lgr	%r1,%r3