minifi-cpp: set CLEANBROKEN to 1

Rebuilding minifi-cpp in old build dir sometimes result
in do_compile failure. So set CLEANBROKEN to "1" to workaround
this problem. If further investigation is done and the underlying
problem is addressed, this setting could be removed.

Signed-off-by: Chen Qi <Qi.Chen@windriver.com>
Signed-off-by: Khem Raj <raj.khem@gmail.com>

meta-oe/recipes-extended/minifi-cpp/minifi-cpp_0.7.0.bb

@@ -139,3 +139,5 @@ pkg_postinst_${PN}() {
         fi
     fi
 }
+
+CLEANBROKEN = "1"