cpu/amd/pi/00730F01: rename fixme.c to cpu_io_init.c

Now that the code is in a much better shape and uses native coreboot
functionality to perform the initialization, rename the file from
fixme.c to cpu_io_init.c to be more descriptive of what it does.

Signed-off-by: Felix Held <felix-coreboot@felixheld.de>
Change-Id: I97d1ac2b12c624210c570f189f825409bd64f318
Reviewed-on: https://review.coreboot.org/c/coreboot/+/74659
Reviewed-by: Martin Roth <martin.roth@amd.corp-partner.google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>

src/cpu/amd/pi/00730F01/Makefile.inc

@@ -1,9 +1,9 @@
 # SPDX-License-Identifier: GPL-2.0-only
 
-romstage-y += fixme.c
+romstage-y += cpu_io_init.c
 
-ramstage-y += fixme.c
 ramstage-y += chip_name.c
+ramstage-y += cpu_io_init.c
 ramstage-y += model_16_init.c
 ramstage-y += update_microcode.c