target-ppc: Introduce and reuse generalized init_proc_book3s_64()

target-ppc: Introduce and reuse generalized init_proc_book3s_64()

At the moment every POWER CPU family has its own init_proc_POWERX function.
E500 already has common init function so we try to do the same thing.

This introduces BOOK3S_CPU_TYPE enum with 2 values - 970 and POWER5+.

This introduces generalized init_proc_book3s_64() which accepts a CPU type
as a parameter.

This uses new init function for 970 and POWER5+ CPU classes.

970 and POWER5+ use the same CPU class initialization except 3 things:
1. logical partitioning is controlled by LPCR (POWER5+) and HID4 (970)
SPRs;
2. 970 does not have EAR (External Access Register) SPR and PowerISA 2.03
defines one so keep it only for POWER5+;
3. POWER5+ does not have ALTIVEC so insns_flags does not have PPC_ALTIVEC
flag set and gen_spr_book3s_altivec() won't init ALTIVEC for POWER5+.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Tom Musta <tommusta@gmail.com>
Signed-off-by: Alexander Graf <agraf@suse.de>