arm: [MVE intrinsics] Add support for predicated contiguous loads and stores

arm: [MVE intrinsics] Add support for predicated contiguous loads and stores

This patch extends
function_expander::use_contiguous_load_insn and
function_expander::use_contiguous_store_insn functions to
support predicated versions.

2024-09-11  Alfie Richards  <Alfie.Richards@arm.com>
	    Christophe Lyon  <christophe.lyon@arm.com>

	gcc/

	* config/arm/arm-mve-builtins.cc
	(function_expander::use_contiguous_load_insn): Add support for
	PRED_z.
	(function_expander::use_contiguous_store_insn): Add support for
	PRED_p.