rs6000: Enforce quad_address_p in TImode atomic_load/store (PR80382)

rs6000: Enforce quad_address_p in TImode atomic_load/store (PR80382)

Whatever expand expands to should be valid instructions.  The defined
instructions here have a quad_memory_operand predicate, which boils
down to quad_address_p on the address, so let's test for that instead
of only disallowing indexed addresses.

	* config/rs6000/sync.md (atomic_load<mode>, atomic_store<mode): Test
	for quad_address_p for TImode, instead of just not indexed_address.

From-SVN: r246867