gst/audiotestsrc/gstaudiotestsrc.*: fixed typo, added pink noise

gst/audiotestsrc/gstaudiotestsrc.*: fixed typo, added pink noise

Original commit message from CVS:
* gst/audiotestsrc/gstaudiotestsrc.c:
(gst_audiostestsrc_wave_get_type), (gst_audiotestsrc_class_init),
(gst_audiotestsrc_init), (gst_audiotestsrc_create_sine),
(gst_audiotestsrc_create_square), (gst_audiotestsrc_create_saw),
(gst_audiotestsrc_create_triangle),
(gst_audiotestsrc_create_silence),
(gst_audiotestsrc_create_white_noise),
(gst_audiotestsrc_init_pink_noise),
(gst_audiotestsrc_generate_pink_noise_value),
(gst_audiotestsrc_create_pink_noise),
(gst_audiotestsrc_change_wave):
* gst/audiotestsrc/gstaudiotestsrc.h:
fixed typo, added pink noise