net: phy: nxp-c45-tja11xx: handle FUSA irq

TJA1120 and TJA1103 have a set of functional safety hardware tests
executed after every reset, and when the tests are done, the IRQ line is
asserted. For the moment, the purpose of these handlers is to acknowledge
the IRQ and not to check the FUSA tests status.

Signed-off-by: Radu Pirea (NXP OSS) <radu-nicolae.pirea@oss.nxp.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lore.kernel.org/r/20230731091619.77961-9-radu-nicolae.pirea@oss.nxp.com


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