target/ppc: Add SRR1 prefix indication to interrupt handlers

target/ppc: Add SRR1 prefix indication to interrupt handlers

ISA v3.1 introduced prefix instructions. Among the changes, various
synchronous interrupts report whether they were caused by a prefix
instruction in (H)SRR1.

The case of instruction fetch that causes an HDSI due to access of a
process-scoped table faulting on the partition scoped translation is the
tricky one. As with ISIs and HISIs, this does not try to set the prefix
bit because there is no instruction image to be loaded. The HDSI needs
the originating access type to be passed through to the handler to
distinguish this from HDSIs that fault translating process scoped tables
originating from a load or store instruction (in that case the prefix
bit should be provided).

Reviewed-by: Fabiano Rosas <farosas@suse.de>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[ clg: checkpatch issues ]
Signed-off-by: Cédric Le Goater <clg@kaod.org>