configure: add const_nan dependency to h264_metadata_bsf

Fixes compilation with some compilers.

Reviewed-by: jkqxz
Signed-off-by: James Almer <jamrial@gmail.com>

configure

@@ -2920,6 +2920,7 @@ vc1_parser_select="vc1dsp"
 # bitstream_filters
 aac_adtstoasc_bsf_select="adts_header"
 filter_units_bsf_select="cbs"
+h264_metadata_bsf_deps="const_nan"
 h264_metadata_bsf_select="cbs_h264"
 h264_redundant_pps_bsf_select="cbs_h264"
 hevc_metadata_bsf_select="cbs_h265"