Split i386.c.

Split i386.c.

2019-05-06  Martin Liska  <mliska@suse.cz>

	* config/i386/i386-builtins.c: New file.
	* config/i386/i386-builtins.h: New file.
	* config/i386/i386-expand.c: New file.
	* config/i386/i386-expand.h: New file.
	* config/i386/i386-features.c: New file.
	* config/i386/i386-features.h: New file.
	* config/i386/i386-options.c: New file.
	* config/i386/i386-options.h: New file.
	* config.gcc: Add new files into extra_objs and
	target_gtfiles.
	* config/i386/i386.c: Split content of the file
	into newly introduced files.
	* config/i386/i386.h: Declare common variables
	and macros.
	* config/i386/t-i386: Define dependencies for new files.

From-SVN: r270895