[FFmpeg-cvslog] Replace 'FontName' with 'Fontname' in the documentation.

[Joe Ratterman]

ffmpeg | branch: master | Joe Ratterman <jratt0 at gmail.com> | Thu May 28 10:31:48 2020 -0700| [c367d14d0a5d4ce1c007f636ba85681915fd5f79] | committer: Gyan Doshi

Replace 'FontName' with 'Fontname' in the documentation.

This is the only use of 'FontName' with that capitalization, as both
source-code and tests use 'Fontname'. Having consistent capitalization
makes it easier to find the relevant source from the docs.

See these examples for other uses:
    libavcodec/ass_split.c:68
    tests/ref/fate/sub-cc:9

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=c367d14d0a5d4ce1c007f636ba85681915fd5f79
---

 doc/filters.texi | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/doc/filters.texi b/doc/filters.texi
index c13b4efacf..f17db3b986 100644
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -17988,7 +17988,7 @@ subtitles=video.mkv:si=1
 To make the subtitles stream from @file{sub.srt} appear in 80% transparent blue
 @code{DejaVu Serif}, use:
 @example
-subtitles=sub.srt:force_style='FontName=DejaVu Serif,PrimaryColour=&HCCFF0000'
+subtitles=sub.srt:force_style='Fontname=DejaVu Serif,PrimaryColour=&HCCFF0000'
 @end example
 
 @section super2xsai