Introduce fold_before_rtl_expansion_p [PR122142]

Introduce fold_before_rtl_expansion_p [PR122142]

As requested in https://inbox.sourceware.org/gcc-patches/CAFiYyc1jzZSZNhTas-DdMBFOzH1p96oGN=OVj6fyjt8HzDUyCA@mail.gmail.com/T/#u.
This introduces fold_before_rtl_expansion_p to replace
`(cfun->curr_properties & PROP_last_full_fold) != 0`.
I am not a fan of include tree-pass.h in gimple-fold.h but that was the
only way to reduce the number of changes.

Bootrapped and tested on x86_64-linux-gnu.

	PR tree-optimization/122142
gcc/ChangeLog:

	* generic-match-head.cc: Include gimple-iterator.h
	and gimple-fold.h.
	* gimple-fold.cc (gimple_fold_builtin_constant_p): Use
	fold_before_rtl_expansion_p.
	(gimple_fold_builtin_assume_aligned): Likewise.
	(gimple_fold_builtin_stdarg): Likewise.
	(gimple_fold_call): Likewise.
	* gimple-fold.h: Include "tree-pass.h".
	(fold_before_rtl_expansion_p): New function.
	* match.pd: Use fold_before_rtl_expansion_p
	instead of `cfun->curr_properties & PROP_last_full_fold`.
	* tree-ssa-forwprop.cc (simplify_builtin_memcmp): Likewise.
	(optimize_stack_restore): Likewise.

Signed-off-by: Andrew Pinski <andrew.pinski@oss.qualcomm.com>