Increase the timeout on 'cpu-mix-test' to accommodate slower machines.

--- pulseaudio-6.0/src/tests/cpu-mix-test.c.ORIG	2015-02-12 09:10:35.000000000 -0500
+++ pulseaudio-6.0/src/tests/cpu-mix-test.c	2015-03-31 13:45:05.316878322 -0400
@@ -212,7 +212,7 @@
 #if defined (__arm__) && defined (__linux__) && defined (HAVE_NEON)
     tcase_add_test(tc, mix_neon_test);
 #endif
-    tcase_set_timeout(tc, 120);
+    tcase_set_timeout(tc, 240);
     suite_add_tcase(s, tc);
 
     sr = srunner_create(s);