Use @xref more consistently; "See @ref" -> "@xref"

Use @xref more consistently; "See @ref" -> "@xref"

* doc/lispref/commands.texi (Using Interactive):
* doc/lispref/customize.texi (Type Keywords):
* doc/lispref/edebug.texi (Using Edebug, Specification List):
* doc/lispref/frames.texi (Frame Layout):
* doc/lispref/functions.texi (What Is a Function, Related Topics):
* doc/lispref/keymaps.texi (Controlling Active Maps, Key Lookup):
* doc/lispref/minibuf.texi (Completion Variables):
* doc/lispref/os.texi (Terminal Input):
* doc/lispref/text.texi (JSONRPC Overview):
* doc/misc/calc.texi (More About Embedded Mode, Customizing Calc):
* doc/misc/cc-mode.texi (Movement Commands, Auto-newlines)
(Config Basics, Custom Auto-newlines):
* doc/misc/gnus.texi (Email Based Diary):
* doc/misc/htmlfontify.texi (Interactive, Non-interactive):
(Variables):
* doc/misc/idlwave.texi (Using the Shell):
* doc/misc/srecode.texi (Quick Start, User Templates)
(Parts of SRecode, Compound Variable Values, Template Macros):
* doc/misc/tramp.texi (Inline methods, FUSE-based methods)
(Predefined connection information, Remote shell setup)
(Frequently Asked Questions):
* doc/misc/transient.texi (Configuration, Technical Introduction):
(Binding Suffix and Infix Commands, Transient State):
(Prefix Slots, Predicate Slots):
* doc/misc/wisent.texi (Example, Compiling a grammar, Conflicts):
(Grammar Debugging, Error recovery):

(cherry picked from commit e54b94c28cdf9699009e7691f7c8ffa5b2c7b741)