Add SymLoadModule64.

dlls/dbghelp/dbghelp.spec

diff --git a/dlls/dbghelp/dbghelp.spec b/dlls/dbghelp/dbghelp.spec
index c3d0c95..6accb2b 100644
--- a/dlls/dbghelp/dbghelp.spec
+++ b/dlls/dbghelp/dbghelp.spec
@@ -70,7 +70,7 @@
 @ stdcall SymGetTypeInfo(ptr long long long long ptr)
 @ stdcall SymInitialize(long str long)
 @ stdcall SymLoadModule(long long str str long long)
-@ stub SymLoadModule64
+@ stdcall SymLoadModule64(long long str str long long long)
 @ stub SymLoadModuleEx
 @ stdcall SymMatchFileName(str str ptr ptr)
 @ stub SymMatchString

dlls/dbghelp/module.c

diff --git a/dlls/dbghelp/module.c b/dlls/dbghelp/module.c
index 208c84c..8cec363 100644
--- a/dlls/dbghelp/module.c
+++ b/dlls/dbghelp/module.c
@@ -374,6 +374,17 @@
     return module->module.BaseOfImage;
 }
 
+/***********************************************************************
+ *                     SymLoadModule64 (DBGHELP.@)
+ */
+DWORD WINAPI SymLoadModule64(HANDLE hProcess, HANDLE hFile, char* ImageName,
+                             char* ModuleName, DWORD64 BaseOfDll, DWORD SizeOfDll)
+{
+    FIXME("SymLoadModule should probably reference SymLoadModule64 instead of this way\n");
+
+    return SymLoadModule(hProcess, hFile, ImageName, ModuleName, (DWORD)BaseOfDll, SizeOfDll);
+}
+
 /******************************************************************
  *		module_remove
  *