Clear hard frame pointer alignment if not needed

Clear hard frame pointer alignment if not needed

When hard frame pointer isn't needed, the register for hard frame pointer
may be reused.  This patch clears alignment on hard frame pointer if hard
frame pointer isn't needed.

gcc/

	PR rtl-optimization/64905
	* lra-eliminations.c (setup_can_eliminate): Clear hard frame
	pointer alignment if it isn't needed.

gcc/testsuite/

	PR rtl-optimization/64905
	* gcc.target/i386/pr64905.c: New file.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@220414 138bc75d-0d04-0410-961f-82ee72b054a4