Add more PPC floating-point conversion instructions

The P7 and A2 have additional floating-point conversion instructions which
allow a direct two-instruction sequence (plus load/store) to convert from all
combinations (signed/unsigned i32/i64) <--> (float/double) (on previous cores,
only some combinations were directly available).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178480 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/PowerPC/PPCSubtarget.cpp b/lib/Target/PowerPC/PPCSubtarget.cpp
index 57e18ed..1b7150f 100644
--- a/lib/Target/PowerPC/PPCSubtarget.cpp
+++ b/lib/Target/PowerPC/PPCSubtarget.cpp
@@ -41,6 +41,7 @@
   , HasSTFIWX(false)
   , HasLFIWAX(false)
   , HasFPRND(false)
+  , HasFPCVT(false)
   , HasISEL(false)
   , HasPOPCNTD(false)
   , HasLDBRX(false)