cgit.c: always setup cgit repo environment variables

When cgit learned to setup environment variables for certain repo
settings before invoking a filter process, the setup occurred inside
cgit_open_filter().

This patch moves the setup out of cgit_open_filter() and into
prepare_repo_cmd() to prepare for additional uses of these variables.

Reviewed-by: Ferry Huberts <mailings@hupie.com>
Signed-off-by: Lars Hjemli <hjemli@gmail.com>

ui-commit.c

@@ -106,7 +106,7 @@ void cgit_print_commit(char *hex, const char *prefix)
 	html("</table>\n");
 	html("<div class='commit-subject'>");
 	if (ctx.repo->commit_filter)
-		cgit_open_filter(ctx.repo->commit_filter, ctx.repo);
+		cgit_open_filter(ctx.repo->commit_filter);
 	html_txt(info->subject);
 	if (ctx.repo->commit_filter)
 		cgit_close_filter(ctx.repo->commit_filter);
@@ -114,7 +114,7 @@ void cgit_print_commit(char *hex, const char *prefix)
 	html("</div>");
 	html("<div class='commit-msg'>");
 	if (ctx.repo->commit_filter)
-		cgit_open_filter(ctx.repo->commit_filter, ctx.repo);
+		cgit_open_filter(ctx.repo->commit_filter);
 	html_txt(info->msg);
 	if (ctx.repo->commit_filter)
 		cgit_close_filter(ctx.repo->commit_filter);
@@ -123,7 +123,7 @@ void cgit_print_commit(char *hex, const char *prefix)
 		html("<div class='notes-header'>Notes</div>");
 		html("<div class='notes'>");
 		if (ctx.repo->commit_filter)
-			cgit_open_filter(ctx.repo->commit_filter, ctx.repo);
+			cgit_open_filter(ctx.repo->commit_filter);
 		html_txt(notes.buf);
 		if (ctx.repo->commit_filter)
 			cgit_close_filter(ctx.repo->commit_filter);