test-lib: on FreeBSD, look for unzip(1) in /usr/local/bin/

Eric Wong reported that while FreeBSD has a /usr/bin/unzip, it uses
different semantics from those that are needed by Git's tests: When
passing the -a option to Info-Zip, it heeds the text attribute of the
.zip file's central directory, while FreeBSD's unzip ignores that
attribute.

The common work-around is to install Info-Zip on FreeBSD, into
/usr/local/bin/.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Tested-by: Eric Wong <e@80x24.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/t/test-lib.sh b/t/test-lib.sh
index cde7fc7..86d77c1 100644
--- a/t/test-lib.sh
+++ b/t/test-lib.sh
@@ -966,7 +966,8 @@
 }
 
 # Fix some commands on Windows
-case $(uname -s) in
+uname_s=$(uname -s)
+case $uname_s in
 *MINGW*)
 	# Windows has its own (incompatible) sort and find
 	sort () {
@@ -1141,6 +1142,7 @@
 	return $status
 '
 
+test FreeBSD != $uname_s || GIT_UNZIP=${GIT_UNZIP:-/usr/local/bin/unzip}
 GIT_UNZIP=${GIT_UNZIP:-unzip}
 test_lazy_prereq UNZIP '
 	"$GIT_UNZIP" -v