Documentation/git-fsck.txt: include fsck.* config variables

The 'fsck.skipList' and 'fsck.<msg-id>' config variables might be
easier to discover when they are documented in 'git fsck's man page.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Author: szeder

Documentation/git-fsck.txt

@@ -104,6 +104,11 @@ care about this output and want to speed it up further.
 	progress status even if the standard error stream is not
 	directed to a terminal.
 
+CONFIGURATION
+-------------
+
+include::config/fsck.txt[]
+
 DISCUSSION
 ----------