Tests: test_suffix.sh: Add a comment

(cherry picked from commit 6167607a6ea72fb74eefb943c4566e3cab528cd2)

diff --git a/tests/test_suffix.sh b/tests/test_suffix.sh
index c01ffb5b9532e57d63452903cd5008ea2ef1f7cc..7fc5996f776269264024df0eb606538963087b47 100755 (executable)
--- a/tests/test_suffix.sh
+++ b/tests/test_suffix.sh
@@ -7,6 +7,9 @@
 #
 ###############################################################################
 
+# Optional argument:
+# $1 = directory of the xz executable
+
 # If xz was not built, skip this test. Autotools and CMake put
 # the xz executable in a different location.
 XZ=${1:-../src/xz}/xz