Add MI "-break-insert --qualified"

Add MI "-break-insert --qualified"

Currently -break-insert always creates a wildmatching breakpoint, and
there's no way to ask for a fullname match.  To address that, this
patch adds the equivalent of "break -qualified" to MI:

  "-break-insert --qualified".

For the testcase, curiously, it doesn't look like we have _any_
testcase that tests a breakpoint with multiple locations, and, the
existing mi_create_breakpoint / mi_make_breakpoint procedures are only
good for breakpoints with a single location.  This patch thus adds a
few new companion routines to mi-support.exp for breakpoints with
multiple locations: mi_create_breakpoint_multi,
mi_make_breakpoint_loc, mi_make_breakpoint_multi.

gdb/ChangeLog:

	* NEWS: Document "-break-insert --qualified".
	* mi/mi-cmd-break.c (mi_cmd_break_insert_1): Handle "--qualified".

gdb/doc/ChangeLog:

	* gdb.texinfo (GDB/MI Breakpoint Commands): Document
	"-break-insert --qualified" and "-dprintf-insert --qualified".

gdb/testsuite/ChangeLog:

	* gdb.mi/mi-break-qualified.cc: New file.
	* gdb.mi/mi-break-qualified.exp: New file.
	* lib/mi-support.exp (mi_create_breakpoint_multi)
	(mi_make_breakpoint_loc, mi_make_breakpoint_multi): New
	procedures.
	(mi_create_breakpoint_1): New, factored out from
	mi_create_breakpoint.