phy: miphy28lp: remove unused struct 'miphy_initval'

'miphy_initval' is unused since the original
commit 2c14e9be ("phy: miphy28lp: Provide support for the MiPHY28lp
Generic PHY").

Remove it.

Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org>
Link: https://lore.kernel.org/r/20240527205844.165279-1-linux@treblig.org


Signed-off-by: Vinod Koul <vkoul@kernel.org>