x86inc.asm: remove redundant ifdef __YASM_VER__

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavutil/x86/x86inc.asm

@@ -632,11 +632,9 @@ SECTION .note.GNU-stack noalloc noexec nowrite progbits
         %elifidn %1, sse3
             %define movu lddqu
         %endif
-        %ifdef __YASM_VER__
         %if notcpuflag(mmx2)
             CPUNOP basicnop
         %endif
-        %endif
     %else
         %xdefine SUFFIX
         %undef cpuname