avcodec/x86/hevc_deblock: use test instead of cmp 0

cherry picked from commit f7843356253459e6010320292dbbc1e888a5249b
Signed-off-by: NMichael Niedermayer <michaelni@gmx.at>

libavcodec/x86/hevc_deblock.asm

@@ -381,7 +381,7 @@ ALIGN 16
     ;compare
     pcmpgtw         m15, m13, m14; beta0, beta1
     movmskps        r13, m15 ;filtering mask 0d0 + 0d3 < beta0 (bit 2 or 3) , 1d0 + 1d3 < beta1 (bit 0 or 1)
-    cmp             r13, 0
+    test            r13, r13
     je              .bypassluma
 
     ;weak / strong decision compare to beta_2