Smake don't include mkdtemp

[Michel Boaventura]

Hello,

make is complaing about an undefined reference to mkdtemp. Smake seems
to include only mkstemp, so I patch it, and it works:

diff --git a/Smake b/Smake
index d700932..10b5124 100644
--- a/Smake
+++ b/Smake
@@ -43,6 +43,7 @@ GNULIB_MODULES = \
        mempcpy \
        memset \
        minmax \
+       mkdtemp \
        mkstemp \
        printf-posix \
        printf-safe \