patch 8.1.0604: autocommand test fails on MS-Windows

Problem:    Autocommand test fails on MS-Windows.
Solution:   Use pathcmp() instead of strcmp() to check if a directory differs.
diff --git a/src/misc2.c b/src/misc2.c
index 4e3b845..060a333 100644
--- a/src/misc2.c
+++ b/src/misc2.c
@@ -3402,7 +3402,7 @@
     vim_strncpy(new_dir, fname, MAXPATHL - 1);
     *gettail_sep(new_dir) = NUL;
 
-    if (STRCMP(old_dir, new_dir) == 0)
+    if (pathcmp((char *)old_dir, (char *)new_dir, -1) == 0)
 	// nothing to do
 	res = OK;
     else