gdb/testsuite/

gdb/testsuite/
	Fix double send_gdb leading to racy FAILs.
	* gdb.base/break.exp (set silent break bp_location1): Replace
	3x send_gdb and gdb_expect by gdb_test.
	* gdb.base/fileio.exp: Replace 2x send_gdb by gdb_exit and sleep.
	* gdb.base/foll-vfork.exp (vfork_and_exec_child_follow_to_main_bp)
	(vfork_and_exec_child_follow_through_step): Use gdb_test_no_output
	instead of send_gdb.  Twice.
	* gdb.base/sepdebug.exp (set silent break bp_location1): Replace
	3x send_gdb and gdb_expect by gdb_test.
	* gdb.mi/mi-nsmoribund.exp: Replace 3x send_gdb by mi_gdb_test.