x86/fpu: Rename 'pcntxt_mask' to 'xfeatures_mask'

So the 'pcntxt_mask' is a misnomer, it's essentially meaningless to anyone
who doesn't know what it does exactly.

Name it more descriptively as 'xfeatures_mask'.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/power/cpu.c

@@ -21,7 +21,7 @@
 #include <asm/xcr.h>
 #include <asm/suspend.h>
 #include <asm/debugreg.h>
-#include <asm/fpu/internal.h> /* pcntxt_mask */
+#include <asm/fpu/internal.h> /* xfeatures_mask */
 #include <asm/cpu.h>
 
 #ifdef CONFIG_X86_32
@@ -225,7 +225,7 @@ static void notrace __restore_processor_state(struct saved_context *ctxt)
 	 * restore XCR0 for xsave capable cpu's.
 	 */
 	if (cpu_has_xsave)
-		xsetbv(XCR_XFEATURE_ENABLED_MASK, pcntxt_mask);
+		xsetbv(XCR_XFEATURE_ENABLED_MASK, xfeatures_mask);
 
 	fix_processor_context();