Most streamers' InitSections just create a text section. Make that the default

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199969 91177308-0d34-0410-b5e6-96231b3b80d8

lib/MC/MCNullStreamer.cpp

@@ -24,9 +24,6 @@ namespace {
     /// @name MCStreamer Interface
     /// @{
 
-    virtual void InitSections() {
-    }
-
     virtual void ChangeSection(const MCSection *Section,
                                const MCExpr *Subsection) {
     }