t: switch $_x40 to $OID_REGEX

Switch all uses of $_x40 to $OID_REGEX so that they work correctly with
larger hashes.  This commit was created by using the following sed
command to modify all files in the t directory except t/test-lib.sh:

  sed -i 's/\$_x40/$OID_REGEX/g'

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/t/diff-lib.sh b/t/diff-lib.sh
index c211dc4..2de880f 100644
--- a/t/diff-lib.sh
+++ b/t/diff-lib.sh
@@ -1,6 +1,6 @@
 :
 
-sanitize_diff_raw='/^:/s/ '"\($_x40\)"' '"\($_x40\)"' \([A-Z]\)[0-9]*	/ \1 \2 \3#	/'
+sanitize_diff_raw='/^:/s/ '"\($OID_REGEX\)"' '"\($OID_REGEX\)"' \([A-Z]\)[0-9]*	/ \1 \2 \3#	/'
 compare_diff_raw () {
     # When heuristics are improved, the score numbers would change.
     # Ignore them while comparing.
@@ -12,7 +12,7 @@
     test_cmp .tmp-1 .tmp-2 && rm -f .tmp-1 .tmp-2
 }
 
-sanitize_diff_raw_z='/^:/s/ '"$_x40"' '"$_x40"' \([A-Z]\)[0-9]*$/ X X \1#/'
+sanitize_diff_raw_z='/^:/s/ '"$OID_REGEX"' '"$OID_REGEX"' \([A-Z]\)[0-9]*$/ X X \1#/'
 compare_diff_raw_z () {
     # When heuristics are improved, the score numbers would change.
     # Ignore them while comparing.