llvm-mc/x86: Fix bug in disambiguation of displacement operand, introduced by me
(I think).
 - We weren't properly parsing the leading parenthesized expression in something
   like 'push (4)(%eax)'.
 
 - Added ParseParenRelocatableExpression to support this. I suspect we should
   just use lookahead, though.

 - Test case to follow.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74685 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/tools/llvm-mc/MC-X86Specific.cpp b/tools/llvm-mc/MC-X86Specific.cpp
index 71d7080..a186618 100644
--- a/tools/llvm-mc/MC-X86Specific.cpp
+++ b/tools/llvm-mc/MC-X86Specific.cpp
@@ -152,7 +152,7 @@
       // memory operand consumed.
     } else {
       // It must be an parenthesized expression, parse it now.
-      if (ParseRelocatableExpression(Disp))
+      if (ParseParenRelocatableExpression(Disp))
         return true;
       
       // After parsing the base expression we could either have a parenthesized