[PATCH] bootstrap: double quote an expression with a wildcard

This prevents from expansion of a wildcard, and find from failing
with the following error.

    find: paths must precede expression

* bootstrap (require_buildreq_patch): Double quote *.diff
* gl/build-aux/bootstrap.in (require_buildreq_patch): Likewise.
---
 bootstrap                 |    2 +-
 gl/build-aux/bootstrap.in |    2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/bootstrap b/bootstrap
index eecab2c..9cbe2fc 100755
--- a/bootstrap
+++ b/bootstrap
@@ -3546,7 +3546,7 @@ func_require_buildreq_patch ()
       # The ugly find invocation is necessary to exit with non-zero
       # status for old find binaries that don't support -exec fully.
       if test ! -d "$local_gl_dir" \
-          || find "$local_gl_dir" -name *.diff -exec false {} \; ; then :
+          || find "$local_gl_dir" -name "*.diff" -exec false {} \; ; then :
       else
           func_append buildreq 'patch - http://www.gnu.org/s/patch
 '
diff --git a/gl/build-aux/bootstrap.in b/gl/build-aux/bootstrap.in
index 266eb20..4d0cabe 100755
--- a/gl/build-aux/bootstrap.in
+++ b/gl/build-aux/bootstrap.in
@@ -1215,7 +1215,7 @@ func_require_buildreq_patch ()
       # The ugly find invocation is necessary to exit with non-zero
       # status for old find binaries that don't support -exec fully.
       if test ! -d "$local_gl_dir" \
-          || find "$local_gl_dir" -name *.diff -exec false {} \; ; then :
+          || find "$local_gl_dir" -name "*.diff" -exec false {} \; ; then :
       else
           func_append buildreq 'patch - http://www.gnu.org/s/patch
 '
-- 
1.7.3.2