MIPS: bpf: Fix branch conditional for BPF_J{GT/GE} cases

The sltiu and sltu instructions will set the scratch register
to 1 if A <= X|K so fix the emitted branch conditional to check
for scratch != zero rather than scratch >= zero which would complicate
the resuling branch logic given that MIPS does not have a BGT or BGET
instructions to compare general purpose registers directly.
Signed-off-by: NMarkos Chandras <markos.chandras@imgtec.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Daniel Borkmann <dborkman@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: netdev@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7126/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

arch/mips/net/bpf_jit.c

@@ -1127,7 +1127,7 @@ static int build_body(struct jit_ctx *ctx)
 				}
 				/* A < (K|X) ? r_scrach = 1 */
 				b_off = b_imm(i + inst->jf + 1, ctx);
-				emit_bcond(MIPS_COND_GT, r_s0, r_zero, b_off,
+				emit_bcond(MIPS_COND_NE, r_s0, r_zero, b_off,
 					   ctx);
 				emit_nop(ctx);
 				/* A > (K|X) ? scratch = 0 */