package/brltty: bump to version 6.3

package/brltty: bump to version 6.3

- Drop second patch (already in version)
- Update hash of README, FrankAudiodata added and update in year:
  https://github.com/brltty/brltty/commit/76852b0214edea71ce36a1f8a905294a164e7f34
  https://github.com/brltty/brltty/commit/fdf19475c9b13125c2b7cb09e7d4c18bdf308e97
  https://github.com/brltty/brltty/commit/8f040b2ab8913b182fb87e3bcfa1f315235120cd
  https://github.com/brltty/brltty/commit/90fd84da90e2354d27a12fbe47728a5491fe8e72
- Update indentation in hash file (two spaces)

https://brltty.app/doc/ChangeLog.txt

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>