sparc: bpf_jit: add support for BPF_LD(X) | BPF_LEN instructions

BPF_LD | BPF_W | BPF_LEN instruction is occasionally used by tcpdump
and present in 11 tests in lib/test_bpf.c
Teach sparc JIT compiler to emit it.
Signed-off-by: NAlexei Starovoitov <ast@plumgrid.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

arch/sparc/net/bpf_jit_comp.c

@@ -624,7 +624,12 @@ void bpf_jit_compile(struct bpf_prog *fp)
 					emit_and(r_A, r_TMP, r_A);
 				}
 				break;
-
+			case BPF_LD | BPF_W | BPF_LEN:
+				emit_skb_load32(len, r_A);
+				break;
+			case BPF_LDX | BPF_W | BPF_LEN:
+				emit_skb_load32(len, r_X);
+				break;
 			case BPF_LD | BPF_IMM:
 				emit_loadimm(K, r_A);
 				break;