Ensure that the undefined __mtfb() primitive is not used on powerpc, from:
https://github.com/libretro/RetroArch/pull/10383

Index: libretro-common/features/features_cpu.c
--- libretro-common/features/features_cpu.c.orig
+++ libretro-common/features/features_cpu.c
@@ -22,6 +22,7 @@
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <sys/time.h>
 
 #if defined(_WIN32)
 #include <direct.h>
