mime_db: Add type for HEVC elementary streams.

"Elementary streams" were introduced with MPEG-2, but did not find much use
outside of internal data interchange until now, which finds some HEVC
files being actually distributed in this format.

The first four bytes (00 00 00 01) are common to all (packetized?) elementary
streams, while the three following (40 01 0c) identify a HEVC stream. Actually
I could not find good data on these; all the HEVC files I saw (and some hex-
dumps on online mailing lists of more) contain these three bytes in common
while following ones appear to be the internal header. (I didn't dig deeply
enough into FFmpeg's source code to find out the "real deal.")

Fixes #12565.

src/data/mime_db/video/hevc

@@ -0,0 +1,14 @@
+
+resource(0, "BEOS:TYPE") #'MIMS' "application/x-vnd.Be-meta-mime";
+
+resource(1, "META:TYPE") "video/hevc";
+
+resource(2, "META:SNIFF_RULE") "0.50 (0x0000000140010c)";
+
+resource(3, "META:S:DESC") #'MSDC' "HEVC elementary stream";
+
+resource(4, "META:EXTENS") message(234) {
+	"extensions" = "hevc",
+	"extensions" = "h265",
+	"type" = "video/hevc"
+};