cvs tests: do not touch test CVS repositories shipped with source

Some tests in t96xx series (cvsimport) want to write into the control area
(CVSROOT) of their test CVS repositories, but this does not work well when
the source area is made read-only (test trash directories are moved via
--root=else/where option).

Copy the supplied test CVS repository to a scratch place at the beginning
of these tests.

Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/lib-cvs.sh

@@ -30,6 +30,12 @@ case "$cvsps_version" in
 	;;
 esac
 
+setup_cvs_test_repository () {
+	CVSROOT="$(pwd)/.cvsroot" &&
+	cp -r "$TEST_DIRECTORY/$1/cvsroot" "$CVSROOT" &&
+	export CVSROOT
+}
+
 test_cvs_co () {
 	# Usage: test_cvs_co BRANCH_NAME
 	rm -rf module-cvs-"$1"