Update kr.m3u

Added links from https://github.com/iptv-org/iptv/issues/1949#issuecomment-812983298

channels/kr.m3u

@@ -79,3 +79,7 @@ http://210.210.155.35/session/0d216142-f3f5-11e8-ab67-89df93dc8d44/dr9445/h/h02/
 http://45.126.83.51/dr9445/h/h02/01.m3u8
 #EXTINF:-1 tvg-id="AniPlus.kr" tvg-name="AniPlus" tvg-country="KR" tvg-language="" tvg-logo="" group-title="",AniPlus (Malay subtitles) (576p)
 http://210.210.155.35/session/0d216142-f3f5-11e8-ab67-89df93dc8d44/dr9445/h/h02/01.m3u8
+#EXTINF:-1 tvg-id="Mnet.kr" tvg-name="Mnet" tvg-country="KR" tvg-language="Korean" tvg-logo="" group-title="",Mnet
+http://95.217.44.77:80/mnet/tracks-v1a1/mono.m3u8
+#EXTINF:-1 tvg-id="SBS.kr" tvg-name="SBS" tvg-country="KR" tvg-language="Korean" tvg-logo="" group-title="",SBS
+http://95.217.44.77:80/sbs/tracks-v1a1/mono.m3u8