Fixed a ton of gcc compile warnings

Removed some unused variables, added some consts, changed some casts
to const_cast. I don't think any of these changes are very
controversial.

Differential Revision: http://reviews.llvm.org/D9674

llvm-svn: 237218
diff --git a/lldb/source/Symbol/CompactUnwindInfo.cpp b/lldb/source/Symbol/CompactUnwindInfo.cpp
index b44568c..dac1287 100644
--- a/lldb/source/Symbol/CompactUnwindInfo.cpp
+++ b/lldb/source/Symbol/CompactUnwindInfo.cpp
@@ -101,7 +101,7 @@
         UNWIND_X86_64_REG_R15        = 5,
         UNWIND_X86_64_REG_RBP        = 6,
     };
-};
+}
 
 
 #ifndef UNWIND_SECOND_LEVEL_REGULAR