net: ethernet: ti: cpsw: fix cpts irq after suspend

net: ethernet: ti: cpsw: fix cpts irq after suspend

Depending on the SoC/platform the CPSW can completely lose context after a
suspend/resume cycle, including CPSW wrapper (WR) which will cause reset of
WR_C0_MISC_EN register, so CPTS IRQ will became disabled.

Fix it by moving CPTS IRQ enabling in cpsw_ndo_open() where CPTS is
actually started.

Fixes: 84ea9c0a95d7 ("net: ethernet: ti: cpsw: enable cpts irq")
Reported-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20201112111546.20343-1-grygorii.strashko@ti.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>