tree-optimization: [PR108684] ICE in verify_ssa due to simple_dce_from_worklist

tree-optimization: [PR108684] ICE in verify_ssa due to simple_dce_from_worklist

In simple_dce_from_worklist, we were removing an inline-asm which had a vdef.
We should not be removing inline-asm which have a vdef as this code
does not check to the store.
This fixes that oversight. This was a latent bug exposed recently
by both VRP and removal of stores to static starting to use
simple_dce_from_worklist.

Committed as approved.
Bootstrapped and tested on x86_64-linux-gnu with no regressions.

	PR tree-optimization/108684

gcc/ChangeLog:

	* tree-ssa-dce.cc (simple_dce_from_worklist):
	Check all ssa names and not just non-vdef ones
	before accepting the inline-asm.
	Call unlink_stmt_vdef on the statement before
	removing it.

gcc/testsuite/ChangeLog:

	* gcc.c-torture/compile/dce-inline-asm-1.c: New test.
	* gcc.c-torture/compile/dce-inline-asm-2.c: New test.
	* gcc.dg/tree-ssa/pr108684-1.c: New test.

co-authored-by: Andrew Macleod  <amacleod@redhat.com>