Typo in subunit developer docs

[Brad Hards]

There is a simple typo in the subunit C bindings documentation.

=== modified file 'c/README'
--- c/README 2009-09-30 12:04:18 +0000
+++ c/README 2010-02-19 05:22:25 +0000
@@ -47,7 +47,7 @@
   if (!result) {
     subunit_test_pass("test name");
   } else {
- subunit_test_failf("test name",
+ subunit_test_fail("test name",
       "Something went wrong running something:\n"
       "exited with result: '%s'", result);
   }