dbghelp: Include port.h for possible alternative to strtoull()

[Andrew Talbot]

Changelog:
    dbghelp: Include port.h for possible alternative to strtoull().

diff --git a/dlls/dbghelp/stabs.c b/dlls/dbghelp/stabs.c
index 889a775..d550633 100644
--- a/dlls/dbghelp/stabs.c
+++ b/dlls/dbghelp/stabs.c
@@ -30,6 +30,7 @@
  */
 
 #include "config.h"
+#include "wine/port.h"
 
 #include <sys/types.h>
 #include <fcntl.h>