x86/fpu: Remove redundant XCOMP_BV initialization

fpu_copy_uabi_to_guest_fpstate() initializes the XCOMP_BV field in the
XSAVE header. That's a leftover from the old KVM FPU buffer handling code.

Since

  d69c138 ("x86/kvm: Convert FPU handling to a single swap buffer")

KVM uses the FPU core allocation code, which initializes the XCOMP_BV
field already.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20220324134623.408932232@linutronix.de

Author: KAGA-KOKO

arch/x86/kernel/fpu/core.c

@@ -415,9 +415,6 @@ int fpu_copy_uabi_to_guest_fpstate(struct fpu_guest *gfpu, const void *buf,
 		xpkru = get_xsave_addr(&kstate->regs.xsave, XFEATURE_PKRU);
 		*vpkru = xpkru->pkru;
 	}
-
-	/* Ensure that XCOMP_BV is set up for XSAVES */
-	xstate_init_xcomp_bv(&kstate->regs.xsave, kstate->xfeatures);
 	return 0;
 }
 EXPORT_SYMBOL_GPL(fpu_copy_uabi_to_guest_fpstate);