The C reimplementation of SYSENTER left that unused ENTRY() label
around. Remove it.

Fixes: 5f310f73 ("x86/entry/32: Re-implement SYSENTER using the new C path")
Originally-by: NPeter Zijlstra <peterz@infradead.org>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NSean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: NAlexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20191023123117.686514045@linutronix.de