[xen master] tools: update configure

[patchbot@xxxxxxx]

commit b1e3a3c874b9bab32cc56820ae3e3d568c120181
Author:     Wei Liu <wl@xxxxxxx>
AuthorDate: Tue Jun 2 17:32:02 2020 +0000
Commit:     Wei Liu <wl@xxxxxxx>
CommitDate: Tue Jun 2 17:55:42 2020 +0000

    tools: update configure
    
    Fixes: e181db8ba4e0 ("m4: use test instead of []")
    Signed-off-by: Wei Liu <wl@xxxxxxx>
---
 tools/configure | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/configure b/tools/configure
index 35036dc1db..3df1a01ff9 100755
--- a/tools/configure
+++ b/tools/configure
@@ -4688,7 +4688,7 @@ for ldflag in $APPEND_LIB
 do
     APPEND_LDFLAGS="$APPEND_LDFLAGS -L$ldflag"
 done
-if  ! -z $EXTRA_PREFIX ; then
+if test ! -z "$EXTRA_PREFIX" ; then
     CPPFLAGS="$CPPFLAGS -I$EXTRA_PREFIX/include"
     LDFLAGS="$LDFLAGS -L$EXTRA_PREFIX/lib"
 fi
--
generated by git-patchbot for /home/xen/git/xen.git#master