enable ssse3 for 64-bit emulator

Change-Id: I6b0c4253a717ce7c39eac5b00f000cfe29d678ab
Signed-off-by: Jason Hu <jia-cheng.hu@intel.com>
diff --git a/target-i386/helper.c b/target-i386/helper.c
index 3e25e3a..388f7a7 100644
--- a/target-i386/helper.c
+++ b/target-i386/helper.c
@@ -146,7 +146,7 @@
             CPUID_MTRR | CPUID_CLFLUSH | CPUID_MCA |
         /* this feature is needed for Solaris and isn't fully implemented */
             CPUID_PSE36,
-        .ext_features = CPUID_EXT_SSE3,
+        .ext_features = CPUID_EXT_SSE3 | CPUID_EXT_SSSE3,
         .ext2_features = (PPRO_FEATURES & 0x0183F3FF) |
             CPUID_EXT2_LM | CPUID_EXT2_SYSCALL | CPUID_EXT2_NX |
             CPUID_EXT2_3DNOW | CPUID_EXT2_3DNOWEXT,