Fix memleak with gst_static_pad_template_get().

Fix memleak with gst_static_pad_template_get().

Original commit message from CVS:
* ext/cairo/gsttextoverlay.c: (gst_text_overlay_init):
* ext/dv/gstdvdemux.c: (gst_dvdemux_init), (gst_dvdemux_add_pads):
* ext/gdk_pixbuf/gstgdkpixbuf.c: (gst_gdk_pixbuf_init):
* ext/jpeg/gstjpegdec.c: (gst_jpeg_dec_init),
(gst_jpeg_dec_setcaps):
* ext/jpeg/gstjpegenc.c: (gst_jpegenc_init):
* ext/jpeg/gstsmokedec.c: (gst_smokedec_init):
* ext/jpeg/gstsmokeenc.c: (gst_smokeenc_init):
* ext/libmng/gstmngdec.c: (gst_mngdec_init),
(gst_mngdec_src_getcaps):
* ext/libpng/gstpngdec.c: (gst_pngdec_init),
(gst_pngdec_caps_create_and_set):
* ext/libpng/gstpngenc.c: (gst_pngenc_init):
* ext/mikmod/gstmikmod.c: (gst_mikmod_init):
* ext/speex/gstspeexdec.c: (gst_speex_dec_init):
* gst/alpha/gstalpha.c: (gst_alpha_init):
* gst/auparse/gstauparse.c: (gst_au_parse_init):
* gst/avi/gstavidemux.c: (gst_avi_demux_init),
(gst_avi_demux_handle_src_event), (gst_avi_demux_parse_stream):
* gst/cutter/gstcutter.c: (gst_cutter_init):
* gst/debug/efence.c: (gst_efence_init), (gst_efence_getrange),
(gst_efence_checkgetrange):
* gst/debug/negotiation.c: (gst_negotiation_init):
* gst/flx/gstflxdec.c: (gst_flxdec_init):
* gst/goom/gstgoom.c: (gst_goom_init):
* gst/rtp/gstasteriskh263.c: (gst_asteriskh263_init):
* gst/rtp/gstrtpL16depay.c: (gst_rtp_L16depay_init):
* gst/rtp/gstrtpL16pay.c: (gst_rtpL16pay_init):
* gst/rtp/gstrtpamrdepay.c: (gst_rtp_amr_depay_init):
* gst/rtp/gstrtpdepay.c: (gst_rtp_depay_init):
* gst/rtp/gstrtpmpadepay.c: (gst_rtp_mpa_depay_init):
* gst/rtsp/gstrtpdec.c: (gst_rtpdec_init):
* gst/smpte/gstsmpte.c: (gst_smpte_init):
* gst/wavparse/gstwavparse.c: (gst_wavparse_init),
(gst_wavparse_create_sourcepad):
Fix memleak with gst_static_pad_template_get().
This uses gst_pad_new_from_static_template() instead.
Fixes #333512