Tighten predicates for p10 ld/cmpi fusion

Tighten predicates for p10 ld/cmpi fusion

PR99070 is caused by a fusion pattern matching that the individual
instructions do not match when it is split later. In this case the
ld+cmpi patterns were allowing a d-form load address, which the split
condition would rightly split, however that left us with something that
could not be matched by a ds-form ld instruction, hence the ICE. This
only happened if the target cpu was not power10 -- if we were targeting
power10 then a prefixed pld instruction would get generated because that
can handle d-form. However this is not optimal code either.

So the solution is a new predicate (ds_form_mem_operand) that only
accepts what we can take as for a ds-form load. Then a small
modification of the genfusion.pl script changes the relevant
ld+cmpi patterns to use the new predicate.

gcc/ChangeLog

	PR target/99070
	* config/rs6000/predicates.md (ds_form_mem_operand) New
	predicate.
	* config/rs6000/genfusion.pl (gen_ld_cmpi_p10) Use
	ds_form_mem_operand in ld/lwa patterns.
	* config/rs6000/fusion.md: Regenerate file.