net: stmmac: use u8 for host_dma_width and similar struct members

net: stmmac: use u8 for host_dma_width and similar struct members

We aren't going to see >= 256-bit address busses soon, so reduce
host_dma_width and associated other struct members that initialise
this from u32 to u8.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Acked-by: Mohd Ayaan Anwar <mohd.anwar@oss.qualcomm.com> # qcom-ethqos
Tested-by: Mohd Ayaan Anwar <mohd.anwar@oss.qualcomm.com>
Link: https://patch.msgid.link/E1vzX5P-0000000CVsK-0iwX@rmk-PC.armlinux.org.uk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>