build: add generated files to .gitignore

Add a batch of files/wildcards to the list of ignored files, so
that "git status" does not show so many files that should be ignored.
The "*.dSYM" directories are generated during building on MacOS.

Signed-off-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
1 file changed