bpf.rst: Point to the right bpf.h file.
bpf.rst: Point to the right bpf.h file.

The reference should be to the uapi/linux/bpf.h instead of linux/bpf.h.

Signed-off-by: Jarno Rajahalme <0f1ab0ac7dffd9db21aa539af2fd4bb04abc3ad4@covalent.io>

mskarbek/cilium,mskarbek/cilium,michi-covalent/cilium,cilium-team/cilium,gumpt/cilium,michi-covalent/cilium,tgraf/cilium,tklauser/cilium,tgraf/cilium,tklauser/cilium,eloycoto/cilium,cilium/cilium,tklauser/cilium,mskarbek/cilium,tgraf/cilium,eloycoto/cilium,cilium/cilium,gumpt/cilium,tgraf/cilium,tklauser/cilium,gumpt/cilium,cilium/cilium,eloycoto/cilium,tgraf/cilium,michi-covalent/cilium,scanf/cilium,eloycoto/cilium,tklauser/cilium,michi-covalent/cilium,scanf/cilium,cilium/cilium,cilium/cilium,mskarbek/cilium,michi-covalent/cilium,mskarbek/cilium,scanf/cilium,tgraf/cilium,scanf/cilium,gumpt/cilium,scanf/cilium,mskarbek/cilium,scanf/cilium,eloycoto/cilium,cilium-team/cilium,gumpt/cilium,gumpt/cilium,gumpt/cilium,eloycoto/cilium,scanf/cilium,eloycoto/cilium