PR/174: petre: The new CSV file identification is returning

"application/csv". According to RFC 4180, the registered mime type
is 'text/csv'. "application/csv" is not registered at all, see
https://www.iana.org/assignments/media-types/media-types.xhtml

src/is_csv.c

@@ -32,7 +32,7 @@
 #include "file.h"
 
 #ifndef lint
-FILE_RCSID("@(#)$File: is_csv.c,v 1.5 2020/06/15 00:56:20 christos Exp $")
+FILE_RCSID("@(#)$File: is_csv.c,v 1.6 2020/08/09 16:43:36 christos Exp $")
 #endif
 
 #include <string.h>
@@ -149,7 +149,7 @@ file_is_csv(struct magic_set *ms, const struct buffer *b, int looks_text)
 		return 1;
 
 	if (mime) {
-		if (file_printf(ms, "application/csv") == -1)
+		if (file_printf(ms, "text/csv") == -1)
 			return -1;
 		return 1;
 	}