x86: Call ix86_access_stack_p only for larger alignment

x86: Call ix86_access_stack_p only for larger alignment

ix86_access_stack_p can be quite expensive.  Don't check symbolic constant
load.  Instead, call ix86_access_stack_p only if an INSN needs alignment
> stack alignment.  This reduces the compile time of PR target/124684 from
185 seconds to 24 seconds.  The compile time of PR target/124165 test is
unchanged.

	PR target/124165
	PR target/124684
	* config/i386/i386.cc (ix86_symbolic_const_load_p_1): Renamed to
	...
	(ix86_need_alignment_p_1): This.
	(ix86_symbolic_const_load_p): Renamed to ...
	(ix86_need_alignment_p): This.
	(ix86_find_max_used_stack_alignment): Call ix86_access_stack_p
	only if the INSN needs alignment > stack alignment.

Signed-off-by: H.J. Lu <hjl.tools@gmail.com>