doc/ffmpeg: do not show examples making use of the deprecated glob_sequence pattern type

The syntax of the 'glob_sequence' pattern type is explained in the image2
manual section, so there is no need to replicate it here.

Also discourage the use of such deprecated pattern type by not showing
examples employing it.

Replace the syntax explanation with an use example of the 'glob' pattern
type.

doc/ffmpeg.texi

@@ -1253,17 +1253,15 @@ composed of three digits padded with zeroes to express the sequence
 number. It is the same syntax supported by the C printf function, but
 only formats accepting a normal integer are suitable.
 
-When importing an image sequence, -i also supports expanding shell-like
-wildcard patterns (globbing) internally. To lower the chance of interfering
-with your actual file names and the shell's glob expansion, you are required
-to activate glob meta characters by prefixing them with a single @code{%}
-character, like in @code{foo-%*.jpeg}, @code{foo-%?%?%?.jpeg} or
-@code{foo-00%[234%]%*.jpeg}.
-If your filename actually contains a character sequence of a @code{%} character
-followed by a glob character, you must double the @code{%} character to escape
-it. Imagine your files begin with @code{%?-foo-}, then you could use a glob
-pattern like @code{%%?-foo-%*.jpeg}. For input patterns that could be both a
-printf or a glob pattern, ffmpeg will assume it is a glob pattern.
+When importing an image sequence, -i also supports expanding
+shell-like wildcard patterns (globbing) internally, by selecting the
+image2-specific @code{-pattern_type glob} option.
+
+For example, for creating a video from filenames matching the glob pattern
+@code{foo-*.jpeg}:
+@example
+ffmpeg -f image2 -pattern_type glob -i 'foo-*.jpeg' -r 12 -s WxH foo.avi
+@end example
 
 @item
 You can put many streams of the same type in the output: