Fix typo: PSYM_ENUMSOURCEFILES_CALLBACK instead of
PSYM_ENUMSOURCFILES_CALLBACK.

diff --git a/include/dbghelp.h b/include/dbghelp.h
index d6c9f44..f19dbc6 100644
--- a/include/dbghelp.h
+++ b/include/dbghelp.h
@@ -742,9 +742,9 @@
 /*************************
  *      Source Files     *
  *************************/
-typedef BOOL (CALLBACK *PSYM_ENUMSOURCFILES_CALLBACK)(PSOURCEFILE, PVOID);
+typedef BOOL (CALLBACK *PSYM_ENUMSOURCEFILES_CALLBACK)(PSOURCEFILE, PVOID);
 
-BOOL WINAPI SymEnumSourceFiles(HANDLE, ULONG64, LPSTR, PSYM_ENUMSOURCFILES_CALLBACK,
+BOOL WINAPI SymEnumSourceFiles(HANDLE, ULONG64, LPSTR, PSYM_ENUMSOURCEFILES_CALLBACK,
                                PVOID);
 BOOL WINAPI SymGetLineFromAddr(HANDLE, DWORD, PDWORD, PIMAGEHLP_LINE);
 BOOL WINAPI SymGetLinePrev(HANDLE, PIMAGEHLP_LINE);