net: ethernet: ti: am65-cpsw: fix memleak in certain XDP cases

In the Linux kernel, the following vulnerability has been resolved: net: ethernet: ti: am65-cpsw: fix memleak in certain XDP cases If the XDP program doesn't result in XDP_PASS then we leak the memory allocated by am65_cpsw_build_skb(). It is pointless to allocate SKB memory before running the XDP program as we would be wasting CPU cycles for cases other than XDP_PASS. Move the SKB allocation after evaluating the XDP program result. This fixes the memleak. A performance boost is seen for XDP_DROP test. XDP_DROP test: Before: 460256 rx/s 0 err/s After: 784130 rx/s 0 err/s