fec: Fix timer capture timing in `fec_ptp_enable_pps()`

Code reimplements functionality already in `fec_ptp_read()`,
but misses check for FEC_QUIRK_BUG_CAPTURE. Replace with function call.

Fixes: 28b5f058 ("net: fec: ptp: fix convergence issue to support LinuxPTP stack")
Signed-off-by: Csókás Bence <csokas.bence@prolan.hu>
Link: https://lore.kernel.org/r/20220811101348.13755-1-csokas.bence@prolan.hu


Signed-off-by: Jakub Kicinski <kuba@kernel.org>