consolidate .gitignore patters into a single file

Signed-off-by: Janne Grunau <janne-ffmpeg@jannau.net>
(cherry picked from commit 2c3589bfda036c7827ded0bf38b16dfe7630bae1)

Signed-off-by: Reinhard Tartler <siretart@tauware.de>
38 files changed