tree-optimization/120089 - force all PHIs live for early-break vect

tree-optimization/120089 - force all PHIs live for early-break vect

The following makes sure to even mark unsupported PHIs live when
doing early-break vectorization since otherwise we fail to validate
we can vectorize those and generate wrong code based on the scalar
PHIs which would only work with a vectorization factor of one.

	PR tree-optimization/120089
	* tree-vect-stmts.cc (vect_stmt_relevant_p): Mark all
	PHIs live when not already so and doing early-break
	vectorization.
	(vect_mark_stmts_to_be_vectorized): Skip virtual PHIs.
	* tree-vect-slp.cc (vect_analyze_slp): Robustify handling
	of early-break forced IVs.

	* gcc.dg/vect/vect-early-break_134-pr120089.c: New testcase.