Simplify references to command line flags.

src/IceRegAlloc.cpp

Index: src/IceRegAlloc.cpp
diff --git a/src/IceRegAlloc.cpp b/src/IceRegAlloc.cpp
index 774815e5aa0e7844ffb065f0da9d0a8de2ffbbdd..2eb3a844b13d8b78e26c12f99e3064739f77c278 100644
--- a/src/IceRegAlloc.cpp
+++ b/src/IceRegAlloc.cpp
@@ -95,7 +95,7 @@ int32_t findMinWeightIndex(
 LinearScan::LinearScan(Cfg *Func)
     : Func(Func), Ctx(Func->getContext()), Target(Func->getTarget()),
       Verbose(BuildDefs::dump() && Func->isVerbose(IceV_LinearScan)),
-      UseReserve(Ctx->getFlags().getRegAllocReserve()) {}
+      UseReserve(getFlags().getRegAllocReserve()) {}
 
 // Prepare for full register allocation of all variables. We depend on liveness
 // analysis to have calculated live ranges.