x86/entry/64: Remove unneeded kernel CR3 switching

When native_load_gs_index() fails on .Lgs_change, CR3 must be kernel
CR3. No need to switch it.
Signed-off-by: NLai Jiangshan <laijs@linux.alibaba.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200419144049.1906-2-laijs@linux.alibaba.com

arch/x86/entry/entry_64.S

@@ -1334,7 +1334,6 @@ SYM_CODE_START_LOCAL(error_entry)
 	 */
 	SWAPGS
 	FENCE_SWAPGS_USER_ENTRY
-	SWITCH_TO_KERNEL_CR3 scratch_reg=%rax
 	jmp .Lerror_entry_done
 
 .Lbstep_iret: