iwx(4): fix xtal latency values

[Stefan Sperling]

While review device-specific quirks in this driver I noticed that
the xtal latency values we send to the chip do no match those used
by the Linux driver.

ok?

diff b81ef55c86817a4ccf18086fd9b7dc3ee49ae415 /usr/src (staged changes)
blob - 096caf79896dcd97f16f0744fb8206ad8a12a9d7
blob + ac55b8e39fe1b6308a9637396caa32f15b5597f7
--- sys/dev/pci/if_iwx.c
+++ sys/dev/pci/if_iwx.c
@@ -9363,7 +9363,7 @@ iwx_attach(struct device *parent, struct device *self,
                sc->sc_integrated = 1;
                sc->sc_ltr_delay = IWX_SOC_FLAGS_LTR_APPLY_DELAY_200;
                sc->sc_low_latency_xtal = 0;
-               sc->sc_xtal_latency = 5000;
+               sc->sc_xtal_latency = 500;
                sc->sc_tx_with_siso_diversity = 0;
                sc->sc_uhb_supported = 0;
                break;
@@ -9373,7 +9373,7 @@ iwx_attach(struct device *parent, struct device *self,
                sc->sc_integrated = 1;
                sc->sc_ltr_delay = IWX_SOC_FLAGS_LTR_APPLY_DELAY_200;
                sc->sc_low_latency_xtal = 0;
-               sc->sc_xtal_latency = 5000;
+               sc->sc_xtal_latency = 1820;
                sc->sc_tx_with_siso_diversity = 0;
                sc->sc_uhb_supported = 0;
                break;