configure: When overriding LIBS, include old $LIBS value.

Fixes commit a4165c822baf74f5c1906593a984f996b11058d1.

diff --git a/configure.ac b/configure.ac
index 6b27aff..aecf96e 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -47,7 +47,7 @@ PKG_CHECK_MODULES([AUGEAS], [augeas])
 
 dnl Check for aug_source function, added in Augeas 1.8.0.
 old_LIBS="$LIBS"
-LIBS="$AUGEAS_LIBS"
+LIBS="$AUGEAS_LIBS $LIBS"
 AC_CHECK_FUNCS([aug_source])
 LIBS="$old_LIBS"