topology: Add ATTRIBUTE_UNUSED for unused parameters to fix compiler warning

topology: Add ATTRIBUTE_UNUSED for unused parameters to fix compiler warning

This commit adds ATTRIBUTE_UNUSED to the unused parameter 'tplg' for
function tplg_parse_streams() and tplg_parse_fe_dai(). These two functions
need to keep 'tplg' as ops for tplg_parse_compound().

The compiler warnings below are fixed:

pcm.c: In function 'tplg_parse_streams':
pcm.c:262:43: warning: unused parameter 'tplg' [-Wunused-parameter]
 static int tplg_parse_streams(snd_tplg_t *tplg, snd_config_t *cfg,
                                           ^
pcm.c: In function 'tplg_parse_fe_dai':
pcm.c:324:42: warning: unused parameter 'tplg' [-Wunused-parameter]
 static int tplg_parse_fe_dai(snd_tplg_t *tplg, snd_config_t *cfg,

Signed-off-by: Mengdong Lin <mengdong.lin@linux.intel.com>
Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>