Fix IsLinux being uninitialized on non-Linux targets.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50660 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86Subtarget.cpp b/lib/Target/X86/X86Subtarget.cpp
index cb07b0d..2dd7b45 100644
--- a/lib/Target/X86/X86Subtarget.cpp
+++ b/lib/Target/X86/X86Subtarget.cpp
@@ -241,6 +241,7 @@
   , X863DNowLevel(NoThreeDNow)
   , HasX86_64(false)
   , DarwinVers(0)
+  , IsLinux(false)
   , stackAlignment(8)
   // FIXME: this is a known good value for Yonah. How about others?
   , MaxInlineSizeThreshold(128)