ART Runtime: Add movb $xx,yy fault handling

Handle a movb $xx,yy instruction in the segmentation violation fault
handler.  This is a simple addition to the '1 byte immediate' opcodes.

This test case shows up in 122-npe using my private backend changes.

Change-Id: I92d816bbf5912135b931f4a76e6c72c0d75eff3b
Signed-off-by: Mark Mendell <mark.p.mendell@intel.com>
diff --git a/runtime/arch/x86/fault_handler_x86.cc b/runtime/arch/x86/fault_handler_x86.cc
index 17310b6..858aeb8 100644
--- a/runtime/arch/x86/fault_handler_x86.cc
+++ b/runtime/arch/x86/fault_handler_x86.cc
@@ -184,6 +184,7 @@
 
       case 0x80:        // group 1, byte immediate.
       case 0x83:
+      case 0xc6:
         modrm = *pc++;
         has_modrm = true;
         immediate_size = 1;