ASoC: hdmi-codec: make const array hdmi_codec_eld_spk_alloc_bits static

Don't populate array hdmi_codec_eld_spk_alloc_bits on the stack but
make it static. Makes the object code smaller by over 260 bytes:

Before:
   text	   data	    bss	    dec	    hex	filename
  10882	   3384	     64	  14330	   37fa	sound/soc/codecs/hdmi-codec.o

After:
   text	   data	    bss	    dec	    hex	filename
  10557	   3440	     64	  14061	   36ed	sound/soc/codecs/hdmi-codec.o

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Mark Brown <broonie@kernel.org>