ipa: Drop the default value of suffix parameter of create_clone (PR119852)

ipa: Drop the default value of suffix parameter of create_clone (PR119852)

In PR 119852 we agreed that since the NULL-ness of the suffix
parameter should prevent creation of a record in the ipa-clones
dump (which is implemented by a previous patch), it should not default
to NULL.

gcc/ChangeLog:

2025-04-25  Martin Jambor  <mjambor@suse.cz>

	PR ipa/119852
	* cgraph.h (cgraph_node::create_clone): Remove the default value of
	argument suffix.  Update function comment.
	* cgraphclones.cc (cgraph_node::create_clone): Update function comment.
	* ipa-inline-transform.cc (clone_inlined_nodes): Pass NULL to suffix
	of create_clone explicitely.
	* ipa-inline.cc (recursive_inlining): Likewise.
	* lto-cgraph.cc (input_node): Likewise.