x86/fpu: Fixup uninitialized feature_name warning

Hand in &feature_name to cpu_has_xfeatures() as it is supposed
to. Fixes an uninitialized warning.
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: brgerst@gmail.com
Cc: dvlasenk@redhat.com
Cc: fenghua.yu@intel.com
Cc: luto@amacapital.net
Cc: tim.c.chen@linux.intel.com
Fixes: d91cab78 ("x86/fpu: Rename XSAVE macros")
Link: http://lkml.kernel.org/r/20150923104901.GA3538@pd.tnicSigned-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/crypto/twofish_avx_glue.c

@@ -558,7 +558,7 @@ static int __init twofish_init(void)
 {
 	const char *feature_name;
 
-	if (!cpu_has_xfeatures(XFEATURE_MASK_SSE | XFEATURE_MASK_YMM, NULL)) {
+	if (!cpu_has_xfeatures(XFEATURE_MASK_SSE | XFEATURE_MASK_YMM, &feature_name)) {
 		pr_info("CPU feature '%s' is not supported.\n", feature_name);
 		return -ENODEV;
 	}