Fix for ldconfig from Ozik (#88)

Author: j-woz

dev/m4/syslibs.m4

@@ -21,7 +21,7 @@ fi
 if [[ ${USE_MAC} == "no" ]]
 then
     # This does not work on the Mac
-    ldconfig -v 2>/dev/null | grep -vP '\t' | cut -d : -f 1 > system-libs.txt
+    ${LDCONFIG} -v 2>/dev/null | grep -vP '\t' | cut -d : -f 1 > system-libs.txt
 else
      touch system-libs.txt
 fi