Use the correct header in the TCG MIPS code to find cacheflush() on OpenBSD.

Use the correct header in the TCG MIPS code to find cacheflush() on OpenBSD
to fix compilation of the MIPS host support for OpenBSD/mips64 based architecures.
Signed-off-by: NBrad Smith <brad@comstyle.com>
Signed-off-by: NAurelien Jarno <aurelien@aurel32.net>

tcg/mips/tcg-target.h

@@ -102,7 +102,11 @@ enum {
 /* guest base is supported */
 #define TCG_TARGET_HAS_GUEST_BASE
 
+#ifdef __OpenBSD__
+#include <machine/sysarch.h>
+#else
 #include <sys/cachectl.h>
+#endif
 
 static inline void flush_icache_range(unsigned long start, unsigned long stop)
 {