[Bug]: gstreamer plugin vapostproc produces tiled output depending on width

### Which component impacted?

Video Processing

### Is it regression? Good in old configuration?

None

### What happened?

Similar to https://github.com/intel/media-driver/issues/1820
Using this pipeline gstreamer:
`gst-launch-1.0 videotestsrc ! video/x-raw,format=BGRx,width=1025,height=768 ! vapostproc ! "video/x-raw(memory:VAMemory),format=NV12" ! vah265lpenc ! h265parse ! matroskamux ! filesink location=test.mkv
` produces a tiled image, while width 1024 works. width=1152 seems to work again.


I also reproduced the issue with an Ultra 7 155H, but there another format is required, since BGRx seems no longer supported on that platform.

### What's the usage scenario when you are seeing the problem?

Transcode for media delivery

### What impacted?

We are currently developing an opensource vdi solution using Flex vGPUs for graphics acceleration and video stream encoding. We need a working video encoding on all resolution, to support dynamic guest resolution.

### Debug Information

1.vainfo: VA-API version: 1.23 (libva 2.22.0)
vainfo: Driver version: Intel iHD driver for Intel(R) Gen Graphics - 25.1.2 ()
2.exists
3.lspci -nn |grep -Ei 'VGA|DISPLAY'
02:00.0 VGA compatible controller [0300]: ASPEED Technology, Inc. ASPEED Graphics Family [1a03:2000] (rev 41)
44:00.0 Display controller [0380]: Advanced Micro Devices, Inc. [AMD/ATI] Arcturus GL-XL [Instinct MI100] [1002:738c] (rev 01)
c4:00.0 Display controller [0380]: Intel Corporation ATS-M [Data Center GPU Flex 170] [8086:56c0] (rev 08)
c4:00.1 Display controller [0380]: Intel Corporation ATS-M [Data Center GPU Flex 170] [8086:56c0] (rev 08)
c4:00.2 Display controller [0380]: Intel Corporation ATS-M [Data Center GPU Flex 170] [8086:56c0] (rev 08)

### Do you want to contribute a patch to fix the issue?

None