[Asm] Add debug tracing in table-generated assembly matcher

This adds debug tracing to the table-generated assembly instruction matcher,
enabled by the -debug-only=asm-matcher option.

The changes in the target AsmParsers are to add an MCInstrInfo reference under
a consistent name, so that we can use it from table-generated code. This was
already being used this way for targets that use deprecation warnings, but 5
targets did not have it, and Hexagon had it under a different name to the other
backends.

llvm-svn: 315445
diff --git a/llvm/lib/Target/Sparc/AsmParser/SparcAsmParser.cpp b/llvm/lib/Target/Sparc/AsmParser/SparcAsmParser.cpp
index 087c037..05f78a4 100644
--- a/llvm/lib/Target/Sparc/AsmParser/SparcAsmParser.cpp
+++ b/llvm/lib/Target/Sparc/AsmParser/SparcAsmParser.cpp
@@ -108,7 +108,7 @@
   SparcAsmParser(const MCSubtargetInfo &sti, MCAsmParser &parser,
                 const MCInstrInfo &MII,
                 const MCTargetOptions &Options)
-      : MCTargetAsmParser(Options, sti), Parser(parser) {
+      : MCTargetAsmParser(Options, sti, MII), Parser(parser) {
     // Initialize the set of available features.
     setAvailableFeatures(ComputeAvailableFeatures(getSTI().getFeatureBits()));
   }