x86/fpu: Inline fpu__xstate_clear_all_cpu_caps()

All fpu__xstate_clear_all_cpu_caps() does is to invoke one simple
function since commit

  73e3a7d2 ("x86/fpu: Remove the explicit clearing of XSAVE dependent features")

so invoke that function directly and remove the wrapper.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190704060743.rvew4yrjd6n33uzx@linutronix.de