net: ena: fix MMIO read buffer leak on probe failure

In the Linux kernel, the following vulnerability has been resolved: net: ena: fix MMIO read buffer leak on probe failure ena_device_init() initializes the MMIO read mechanism with ena_com_mmio_reg_read_request_init(), which allocates a coherent DMA buffer for MMIO read responses. The normal removal path releases this buffer through ena_com_mmio_reg_read_request_destroy(). However, if ena_probe() fails after ena_device_init() succeeds, the error path destroys the admin resources and eventually frees ena_dev without destroying the MMIO read request, leaving the coherent DMA buffer allocated. Call ena_com_mmio_reg_read_request_destroy() in the probe error path before releasing the remaining device resources. This issue was found by manual code inspection.