analyzer: move known funs for fds to sm-fd.cc

analyzer: move known funs for fds to sm-fd.cc

This mostly mechanical change enables a simplification in the
followup patch.  No functional change intended.

gcc/analyzer/ChangeLog:
	* analyzer.h (register_known_fd_functions): New decl.
	* region-model-impl-calls.cc (class kf_accept): Move to sm-fd.cc.
	(class kf_bind): Likewise.
	(class kf_connect): Likewise.
	(class kf_listen): Likewise.
	(class kf_pipe): Likewise.
	(class kf_socket): Likewise.
	(register_known_functions): Remove registration of the above
	functions, instead calling register_known_fd_functions.
	* sm-fd.cc: Include "analyzer/call-info.h".
	(class kf_socket): Move here from region-model-impl-calls.cc.
	(class kf_bind): Likewise.
	(class kf_listen): Likewise.
	(class kf_accept): Likewise.
	(class kf_connect): Likewise.
	(class kf_pipe): Likewise.
	(register_known_fd_functions): New.

Signed-off-by: David Malcolm <dmalcolm@redhat.com>