c++: pragma target and static init [PR109753]

c++: pragma target and static init [PR109753]

 #pragma target and optimize should also apply to implicitly-generated
 functions like static initialization functions and defaulted special member
 functions.

The handle_optimize_attribute change is necessary to avoid regressing
g++.dg/opt/pr105306.C; maybe_clone_body creates a cgraph_node for the ~B
alias before handle_optimize_attribute, and the alias never goes through
finalize_function, so we need to adjust semantic_interposition somewhere
else.

	PR c++/109753

gcc/c-family/ChangeLog:

	* c-attribs.cc (handle_optimize_attribute): Set
	cgraph_node::semantic_interposition.

gcc/cp/ChangeLog:

	* decl.cc (start_preparsed_function): Call decl_attributes.

gcc/testsuite/ChangeLog:

	* g++.dg/opt/always_inline1.C: New test.