error finding pkcs11 on Mac

ax_init_standard_project.m4

@@ -366,7 +366,8 @@ AC_DEFUN([AX_PKG_REQUIRE], [
         for p in /usr/include ${$1_CFLAGS}; do
           $1_file=$(find ${p#-I} -name $3)
           if test -e ${$1_file}; then
-            $1_CFLAGS="${$1_CFLAGS} -I${$1_file%/*}"
+            AC_MSG_WARN([Header file $3 found as ${$1_file} in ${$1_file%/$3}])
+            $1_CFLAGS="${$1_CFLAGS} -I${$1_file%/$3}"
             $1_found=1
             break
           fi