Merge branch 'jc/hold-diff-remove-q-synonym-for-no-deletion'

Remove a confusing and deprecated "-q" option from "git diff-files";
"git diff-files --diff-filter=d" can be used instead.

diff.h

@@ -345,8 +345,6 @@ extern int parse_rename_score(const char **cp_p);
 
 extern long parse_algorithm_value(const char *value);
 
-extern void handle_deprecated_show_diff_q(struct diff_options *);
-
 extern int print_stat_summary(FILE *fp, int files,
 			      int insertions, int deletions);
 extern void setup_diff_pager(struct diff_options *);