s390/head64: remove unnecessary vdso_per_cpu_data setup

vdso_per_cpu_data lowcore value is only needed for fully functional
exception handlers, which are activated in setup_lowcore_dat_off. The
same function does init vdso_per_cpu_data via vdso_alloc_boot_cpu.
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

arch/s390/kernel/head64.S

@@ -26,8 +26,6 @@ ENTRY(startup_continue)
 0:	larl	%r1,tod_clock_base
 	mvc	0(16,%r1),__LC_BOOT_CLOCK
 	larl	%r13,.LPG1		# get base
-	larl	%r0,boot_vdso_data
-	stg	%r0,__LC_VDSO_PER_CPU
 #
 # Setup stack
 #