Fix some incorrect uses of the ok macro where the result depends on
the evaluation order of its arguments.

diff --git a/dlls/kernel/tests/file.c b/dlls/kernel/tests/file.c
index 3c1d17b..92ae9bf 100644
--- a/dlls/kernel/tests/file.c
+++ b/dlls/kernel/tests/file.c
@@ -571,9 +571,11 @@
        "WriteFile error %ld\n", GetLastError());
     ok(GetFileSize(hfile, NULL) == sizeof(prefix), "source file has wrong size\n");
     /* get the file time and change it to prove the difference */
-    ok(GetFileTime(hfile, NULL, NULL, &ft1), "GetFileTime error %ld\n", GetLastError());
+    ret = GetFileTime(hfile, NULL, NULL, &ft1);
+    ok( ret, "GetFileTime error %ld\n", GetLastError());
     ft1.dwLowDateTime -= 600000000; /* 60 second */
-    ok(SetFileTime(hfile, NULL, NULL, &ft1), "SetFileTime error %ld\n", GetLastError());
+    ret = SetFileTime(hfile, NULL, NULL, &ft1);
+    ok( ret, "SetFileTime error %ld\n", GetLastError());
     GetFileTime(hfile, NULL, NULL, &ft1);  /* get the actual time back */
     CloseHandle(hfile);
 
@@ -595,7 +597,8 @@
     ok(ret == sizeof(prefix), "destination file has wrong size %ld\n", ret);
 
     /* make sure that destination has the same filetime */
-    ok(ret = GetFileTime(hfile, NULL, NULL, &ft2), "GetFileTime error %ld\n", GetLastError());
+    ret = GetFileTime(hfile, NULL, NULL, &ft2);
+    ok( ret, "GetFileTime error %ld\n", GetLastError());
     ok(CompareFileTime(&ft1, &ft2) == 0, "destination file has wrong filetime\n");
 
     SetLastError(0xdeadbeef);