x86/fpu: Cleanup fpu__init_system_xstate_size_legacy()

mainline inclusion
from mainline-v5.16-rc1
commit 617473ac
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit 617473ac x86/fpu: Cleanup fpu__init_system_xstate_size_legacy().
--------------------------------

Clean the function up before making changes.

No functional change.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20211014230739.184014242@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>
Signed-off-by: NAichun Shi <aichun.shi@intel.com>

arch/x86/kernel/fpu/init.c

@@ -199,17 +199,12 @@ static void __init fpu__init_system_xstate_size_legacy(void)
 	 * Note that xstate sizes might be overwritten later during
 	 * fpu__init_system_xstate().
 	 */
-
-	if (!boot_cpu_has(X86_FEATURE_FPU)) {
+	if (!cpu_feature_enabled(X86_FEATURE_FPU))
 		fpu_kernel_xstate_size = sizeof(struct swregs_state);
-	} else {
-		if (boot_cpu_has(X86_FEATURE_FXSR))
-			fpu_kernel_xstate_size =
-				sizeof(struct fxregs_state);
-		else
-			fpu_kernel_xstate_size =
-				sizeof(struct fregs_state);
-	}
+	else if (cpu_feature_enabled(X86_FEATURE_FXSR))
+		fpu_kernel_xstate_size = sizeof(struct fxregs_state);
+	else
+		fpu_kernel_xstate_size = sizeof(struct fregs_state);
 
 	fpu_user_xstate_size = fpu_kernel_xstate_size;
 	fpstate_reset(&current->thread.fpu);