Revert "LivePhysRegs: Skip reserved regs in computeLiveIns; NFCI"

Tentatively revert, suspecting that it caused breakage in stage2
buildbots.

This reverts commit r303949.
This reverts commit r303937.

llvm-svn: 303955
diff --git a/llvm/lib/CodeGen/BranchRelaxation.cpp b/llvm/lib/CodeGen/BranchRelaxation.cpp
index feaabb4..7af1369 100644
--- a/llvm/lib/CodeGen/BranchRelaxation.cpp
+++ b/llvm/lib/CodeGen/BranchRelaxation.cpp
@@ -259,7 +259,7 @@
 
   // Need to fix live-in lists if we track liveness.
   if (TRI->trackLivenessAfterRegAlloc(*MF))
-    computeLiveIns(LiveRegs, MF->getRegInfo(), *NewBB);
+    computeLiveIns(LiveRegs, *TRI, *NewBB);
 
   ++NumSplit;