[PR103302] skip multi-word pre-move clobber during lra

[PR103302] skip multi-word pre-move clobber during lra

If we emit clobbers before multi-word moves during lra, we get
confused if a copy ends up with input or output replaced with each
other: the clobber then kills the previous set, and it gets deleted.

This patch avoids emitting such clobbers when lra_in_progress.

for  gcc/ChangeLog

	PR target/103302
	* expr.c (emit_move_multi_word): Skip clobber during lra.

for  gcc/testsuite/ChangeLog

	PR target/103302
	* gcc.target/riscv/pr103302.c: New.