config AX88796B_PHY
	tristate "Asix PHYs"
	help
	  Currently supports the Asix Electronics PHY found in the X-Surf 100
	  AX88796B package.

config AX88796B_RUST_PHY
	bool "Rust reference driver"
	depends on RUST && AX88796B_PHY
	default n
	help
	  Uses the Rust version driver for Asix PHYs.


The problem is that there are NIC drivers that `select
AX88796B_PHY`. the Kconfig language doesn't support something like
`select AX88796B_PHY or AX88796B_RUST_PHY`, I guess.

So change AX88796B_PHY to mean any driver for that hardware. And then
move the C driver to AX88796B_C_PHY, and add AX88796B_RUST_PHY.

All the MAC drivers really cares about is that there is a PHY
driver. They don't care if it is written in C, Rust, or SNOBOL.

	Andrew