anx3429: read chip firmware version during init
anx3429: read chip firmware version during init

fetching the chip firmware version toward the end of the chip
anx74xx_tcpm_init() sequence is a good place to do this.  we need this
info in any case and this is a safe place to access device registers
and cache the values.  subsequent chip firmware queries typically
return the cached value.  also, tcpci_tcpm_init() is already
structured this way.

TEST=verified with follow-up CL that firmware update succeeds and new
	version is reported

BRANCH=none
BUG=b:35586895

Change-Id: Ic3fd07bbf8a220bfd506d59d8a1f3ea25b14e94c
Signed-off-by: Caveh Jalali <08e24a66aefda7a55ca7d73f8903e0fb16eec763@google.com>
Reviewed-on: https://chromium-review.googlesource.com/634513
Reviewed-by: Shawn N <5259333ce42e3ace6a73988cec7115ed9d3a661a@chromium.org>

coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec