Fix PDB/func-symbols.test for Arm/Windows

PDB/func-symbols.test was orignally written for 32bit x86, keeping in
mind cdecl and stdcall calling conventions which does name mangling for
example like adding "_" underscore before function name.
This is only x86 specific but purpose of pointers.test is NOT to test
calling convention.
I have made a minor change to make this test pass on Windows/Arm.

lldb/test/Shell/SymbolFile/PDB/func-symbols.test

@@ -27,7 +27,7 @@ CHECK-ONE-DAG: Function{[[UID1]]}, mangled = ?Func_arg_void@@YAXXZ, demangled =
 CHECK-ONE-DAG: Function{[[UID2]]}, mangled = ?Func_arg_none@@YAXXZ, demangled = {{.*}}, type = [[TY2]]
 CHECK-ONE-DAG: Function{[[UID3]]}, mangled = ?Func_varargs@@YAXZZ, demangled = {{.*}}, type = [[TY3]]
 CHECK-ONE-DAG: Function{[[UID4]]}, mangled = ?Func@NS@@YAXDH@Z, demangled = {{.*}}, type = [[TY4]]
-CHECK-ONE-DAG: Function{[[UID5]]}, mangled = _main, demangled = {{.*}}, type = [[TY5]]
+CHECK-ONE-DAG: Function{[[UID5]]}, mangled = {{_?}}main, demangled = {{.*}}, type = [[TY5]]
 CHECK-ONE-DAG: Function{[[UID6]]}, demangled = {{.*}}`anonymous namespace'::Func{{.*}}, type = [[TY6]]
 CHECK-ONE-DAG: Function{[[UID7]]}, demangled = {{.*}}StaticFunction{{.*}}, type = [[TY7]]
 CHECK-ONE-DAG: Function{[[UID8]]}, mangled = ?Func@A@MemberTest@@QAAHHZZ, demangled = {{.*}}, type = [[TY8]]