[Sparc] Add support for the partial write PSR instruction

Summary:
Partial write %PSR (WRPSR) is a SPARC V8e option that allows WRPSR
instructions to only affect the %PSR.ET field. It is supported by
the GR740 and GR716.

Reviewers: jyknight, venkatra

Subscribers: fedor.sergeev, jrtc27, llvm-commits

Differential Revision: https://reviews.llvm.org/D48644

llvm-svn: 343202
diff --git a/llvm/lib/Target/Sparc/SparcSubtarget.cpp b/llvm/lib/Target/Sparc/SparcSubtarget.cpp
index f3a2049..5301fc3 100644
--- a/llvm/lib/Target/Sparc/SparcSubtarget.cpp
+++ b/llvm/lib/Target/Sparc/SparcSubtarget.cpp
@@ -44,6 +44,7 @@
   // Leon features
   HasLeonCasa = false;
   HasUmacSmac = false;
+  HasPWRPSR = false;
   InsertNOPLoad = false;
   FixAllFDIVSQRT = false;
   DetectRoundChange = false;