target/ppc: Fix MPC8555 and MPC8560 core type to e500v1

target/ppc: Fix MPC8555 and MPC8560 core type to e500v1

Commit 80d11f4467c4 ("Add definitions for Freescale PowerPC implementations")
changed core type of MPC8555 and MPC8560 from e500v1 to e500v2.

But both MPC8555 and MPC8560 have just e500v1 cores, there are no features
of e500v2 cores. It can be verified by reading NXP documentations:
https://www.nxp.com/docs/en/data-sheet/MPC8555EEC.pdf
https://www.nxp.com/docs/en/data-sheet/MPC8560EC.pdf
https://www.nxp.com/docs/en/reference-manual/MPC8555ERM.pdf
https://www.nxp.com/docs/en/reference-manual/MPC8560RM.pdf

Therefore fix core type of MPC8555 and MPC8560 back to e500v1.

Just for completeness, here is list of all Motorola/Freescale/NXP
processors which were released and have e500v1 or e500v2 cores:

e500v1: MPC8540 MPC8541 MPC8555 MPC8560

e500v2: BSC9131 BSC9132
        C291 C292 C293
        MPC8533 MPC8535 MPC8536 MPC8543 MPC8544 MPC8545 MPC8547
        MPC8548 MPC8567 MPC8568 MPC8569 MPC8572
        P1010 P1011 P1012 P1013 P1014 P1015 P1016 P1020 P1021
        P1022 P1024 P1025 P2010 P2020

Sorted alphabetically; not by release date / generation / feature set.
All this is from public information available on NXP website.

Seems that qemu has support only for some subset of MPC85xx processors.
Historically processors with e500 cores have mpc85xx family codename and
lot of software have them in mpc85xx architecture subdirectory.

Note that GCC uses -mcpu=8540 option for specifying e500v1 core and
-mcpu=8548 option for specifying e500v2 core.

So sometimes (mpc)8540 is alias for e500v1 and (mpc)8548 is alias for
e500v2.

Fixes: 80d11f4467c4 ("Add definitions for Freescale PowerPC implementations")
Signed-off-by: Pali Rohár <pali@kernel.org>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20220703195029.23793-1-pali@kernel.org>
[danielhb: added more context in the commit msg]
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>