[PR123922, LRA]: Fix asan related bug in LRA

[PR123922, LRA]: Fix asan related bug in LRA

LRA rarely splits hard reg live ranges to assign regs to pseudos when
other possibility to allocate regs failed.  During the pseudo
assignment LRA updates hard reg preferences of pseudos connected to
given pseudo through copies.  For this LRA uses array
update_hard_regno_preference_check which was not allocated during hard
reg live range splitting.  The patch fixes the bug by allocation of
the array during hard reg live range splitting.

gcc/ChangeLog:

	PR rtl-optimization/123922
	* lra-assigns.cc (lra_split_hard_reg_for): Allocate and free
	update_hard_regno_preference_check.  Clear non_reload_pseudos for
	successful spilling too.