configure: check yasm/nasm for working pextrd opcode

NASM versions older than 2.08 fail to build ffmpeg with several
"error: operation size not specified" errors but this is not caught in
configure.

Fix that by checking if "pextrd [eax], xmm0, 1" works in configure.
Signed-off-by: Ronald S. Bultje <rsbultje@gmail.com>

configure

@@ -2671,7 +2671,7 @@ EOF
             elf*) enabled debug && append YASMFLAGS $yasm_debug ;;
         esac
 
-        check_yasm "pabsw xmm0, xmm0" && enable yasm ||
+        check_yasm "pextrd [eax], xmm0, 1" && enable yasm ||
             die "yasm not found, use --disable-yasm for a crippled build"
     fi