Account for calling convention specifiers in function definitions in IR test cases

Several tests wouldn't pass when executed on an armv7a_pc_linux triple
due to the non-default arm_aapcs calling convention produced on the
function definitions in the IR output. Account for this with the
application of a little regex.

Patch by Ying Yi.

llvm-svn: 240971
diff --git a/clang/test/CodeGenCXX/derived-to-virtual-base-class-calls-final.cpp b/clang/test/CodeGenCXX/derived-to-virtual-base-class-calls-final.cpp
index dd64e81..3a4766d 100644
--- a/clang/test/CodeGenCXX/derived-to-virtual-base-class-calls-final.cpp
+++ b/clang/test/CodeGenCXX/derived-to-virtual-base-class-calls-final.cpp
@@ -9,7 +9,7 @@
   virtual void f();
 };
 
-// CHECK-LABEL: define dereferenceable({{[0-9]+}}) %struct.B* @_Z1fR1D
+// CHECK-LABEL: define {{.*}}dereferenceable({{[0-9]+}}) %struct.B* @_Z1fR1D
 B &f(D &d) {
   // CHECK-NOT: load i8*, i8**
   return d;