x86/entry/64: Remove an unused label

The label .Lcommon_\sym was introduced by 39e95433.
(x86-64: Reduce amount of redundant code generated for invalidate_interruptNN)
And all the other relevant information was removed by 52aec330
(x86/tlb: replace INVALIDATE_TLB_VECTOR by CALL_FUNCTION_VECTOR)

Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200419144049.1906-4-laijs@linux.alibaba.com